Day 20 completed

The key feature for part 2 is changing up what the Dijkstra solver views as an "adjacent" node, injecting the appropriate depth as we traverse inner/outer portals. The main thing that tripped me up here from part 1 was that I needed to be carrying more data along with portals than just their locations, and I could no longer get away with storing the portals as pairs of their inner/outer locations, so a small refactor was needed. Once I made those corrections, it was mostly a matter of ironing out the "get neighbors" function to adhere to part 2's rules, which took me a lot of debugging to get just right.
Day 20 part 1
2022-06-22 23:32:33 -05:00 · 2022-06-22 16:53:03 -05:00 · 2022-06-22 16:52:32 -05:00 · 2022-06-22 16:52:32 -05:00 · 2022-06-22 16:52:25 -05:00 · 2022-06-22 16:52:18 -05:00
28 changed files with 1774 additions and 35 deletions
--- a/.gitignore
+++ b/.gitignore
@ -2,3 +2,4 @@
 __debug_bin
 aoc2019
 debug.test
+*.*prof
--- a/days/14.go
+++ b/days/14.go
@ -104,26 +104,10 @@ func (d *Day14) Part1() string {
 func (d *Day14) Part2() string {
 	oreAvailable := int64(1000000000000)
 	estimate := oreAvailable / d.getOreRequiredForFuel(1)
-
-	high := estimate * 2
-	low := estimate
-
-	lastSuccess := low
-	lastFailure := high
-	fuelProduced := low
-
-	for math.Abs(float64(lastFailure-lastSuccess)) > 1 {
-		oreConsumed := d.getOreRequiredForFuel(fuelProduced)
-		adjustment := (lastFailure - lastSuccess) / 2
-		if oreConsumed < oreAvailable {
-			lastSuccess = fuelProduced
-		} else {
-			lastFailure = fuelProduced
-			adjustment = -adjustment
-		}
-
-		fuelProduced += adjustment
-	}
+	lastSuccess := u.Bisect(estimate, estimate*2, 1, func(val int64) bool {
+		oreConsumed := d.getOreRequiredForFuel(val)
+		return oreConsumed < oreAvailable
+	})

 	return fmt.Sprintf("Maximum fuel we can make from 1 trillion ore: %s%d%s", u.TextBold, lastSuccess, u.TextReset)
 }
--- a/days/17.go
+++ b/days/17.go
@ -0,0 +1,422 @@
+package days
+
+import (
+	"fmt"
+	"strings"
+
+	u "parnic.com/aoc2019/utilities"
+)
+
+type camViewCellType int
+type botFacing int
+type day17Grid [][]camViewCellType
+
+const (
+	cellTypeScaffold camViewCellType = iota
+	cellTypeOpen
+	cellTypeInvalid
+)
+
+const (
+	botFacingUp botFacing = iota
+	botFacingLeft
+	botFacingDown
+	botFacingRight
+
+	botFacingFirst = botFacingUp
+	botFacingLast  = botFacingRight
+)
+
+const (
+	dirLeft                 = 1
+	dirRight                = -1
+	maxInstructionSetLength = 20
+)
+
+var (
+	day17AdjacentOffsets = []u.Vec2i{
+		{X: -1, Y: 0},
+		{X: 1, Y: 0},
+		{X: 0, Y: -1},
+		{X: 0, Y: 1},
+	}
+)
+
+type Day17 struct {
+	program u.IntcodeProgram
+}
+
+func (d *Day17) Parse() {
+	d.program = u.LoadIntcodeProgram("17p")
+}
+
+func (d Day17) Num() int {
+	return 17
+}
+
+func (currentDir botFacing) getNewFacingDir(turnDir int) botFacing {
+	currentDir += botFacing(turnDir)
+	if currentDir < botFacingFirst {
+		currentDir = botFacingLast
+	} else if currentDir > botFacingLast {
+		currentDir = botFacingFirst
+	}
+
+	return currentDir
+}
+
+func (grid day17Grid) Draw(botLocation u.Vec2i, botFacingDir botFacing, endLocation u.Vec2i) {
+	for y := range grid {
+		for x := range grid[y] {
+			switch grid[y][x] {
+			case cellTypeOpen:
+				fmt.Print(" ")
+			case cellTypeScaffold:
+				char := "█"
+				color := u.ColorBlack
+				if botLocation.X == x && botLocation.Y == y {
+					switch botFacingDir {
+					case botFacingUp:
+						char = "^"
+					case botFacingLeft:
+						char = "<"
+					case botFacingDown:
+						char = "v"
+					case botFacingRight:
+						char = ">"
+					}
+				} else if endLocation.X == x && endLocation.Y == y {
+					char = "@"
+				} else {
+					color = u.ColorWhite
+				}
+				fmt.Printf("%s%s%s%s", u.BackgroundWhite, color, char, u.TextReset)
+			}
+		}
+		fmt.Println()
+	}
+}
+
+func (grid day17Grid) getAdjacentScaffolds(y, x int) []u.Vec2i {
+	retval := make([]u.Vec2i, 0)
+	for _, offset := range day17AdjacentOffsets {
+		offY := y + offset.Y
+		offX := x + offset.X
+		if offY < 0 || offY >= len(grid) ||
+			offX < 0 || offX >= len(grid[0]) {
+			continue
+		}
+
+		if grid[offY][offX] == cellTypeScaffold {
+			retval = append(retval, u.Vec2i{X: offX, Y: offY})
+		}
+	}
+
+	return retval
+}
+
+func (grid day17Grid) forEachCellOfType(t camViewCellType, f func(y, x int)) {
+	for y := range grid {
+		for x := range grid[y] {
+			if grid[y][x] == t {
+				f(y, x)
+			}
+		}
+	}
+}
+
+func (grid *day17Grid) processGridUpdate(y int, rVal rune, currBotLocation u.Vec2i, currBotFacing botFacing) (int, u.Vec2i, botFacing) {
+	grid.appendValue(rVal, y)
+
+	switch rVal {
+	case '\n':
+		y++
+	case '^', '<', 'v', '>':
+		currBotLocation = u.Vec2i{X: len((*grid)[y]) - 1, Y: y}
+		switch rVal {
+		case '^':
+			currBotFacing = botFacingUp
+		case '<':
+			currBotFacing = botFacingLeft
+		case 'v':
+			currBotFacing = botFacingDown
+		case '>':
+			currBotFacing = botFacingRight
+		}
+	}
+
+	return y, currBotLocation, currBotFacing
+}
+
+func (grid day17Grid) getCellTypeInDirection(y, x int, facingDir botFacing) (camViewCellType, int, int) {
+	newX := x
+	newY := y
+	switch facingDir {
+	case botFacingUp:
+		newY--
+	case botFacingLeft:
+		newX--
+	case botFacingDown:
+		newY++
+	case botFacingRight:
+		newX++
+	}
+
+	if newY < 0 || newY >= len(grid) || newX < 0 || newX >= len(grid[0]) {
+		return cellTypeInvalid, newY, newX
+	}
+
+	return grid[newY][newX], newY, newX
+}
+
+func (grid *day17Grid) appendValue(rVal rune, row int) {
+	ensureCapacity := func(y int) {
+		for len(*grid) <= y {
+			*grid = append(*grid, make([]camViewCellType, 0))
+		}
+	}
+
+	switch rVal {
+	case '#':
+		ensureCapacity(row)
+		(*grid)[row] = append((*grid)[row], cellTypeScaffold)
+	case '.':
+		ensureCapacity(row)
+		(*grid)[row] = append((*grid)[row], cellTypeOpen)
+	case '^', '<', 'v', '>':
+		ensureCapacity(row)
+		(*grid)[row] = append((*grid)[row], cellTypeScaffold)
+	}
+}
+
+func (grid day17Grid) findEndLocation(botLocation u.Vec2i) u.Vec2i {
+	var endLocation u.Vec2i
+	grid.forEachCellOfType(cellTypeScaffold, func(y, x int) {
+		if numSurrounding := len(grid.getAdjacentScaffolds(y, x)); numSurrounding == 1 {
+			if botLocation.X != x || botLocation.Y != y {
+				endLocation = u.Vec2i{X: x, Y: y}
+			}
+		}
+	})
+
+	return endLocation
+}
+
+func (grid day17Grid) getTurnDirectionFromCorner(pos u.Vec2i, botFacingDir botFacing) (int, string) {
+	adj := grid.getAdjacentScaffolds(pos.Y, pos.X)
+	turnDirection := 0
+	// this is so awful. i'm sure there's a better way, but i'm tired.
+	if botFacingDir == botFacingUp || botFacingDir == botFacingDown {
+		if u.ArrayContains(adj, u.Vec2i{X: pos.X - 1, Y: pos.Y}) {
+			if botFacingDir == botFacingUp {
+				turnDirection = dirLeft
+			} else if botFacingDir == botFacingDown {
+				turnDirection = dirRight
+			}
+		} else if u.ArrayContains(adj, u.Vec2i{X: pos.X + 1, Y: pos.Y}) {
+			if botFacingDir == botFacingUp {
+				turnDirection = dirRight
+			} else if botFacingDir == botFacingDown {
+				turnDirection = dirLeft
+			}
+		}
+	} else {
+		if u.ArrayContains(adj, u.Vec2i{X: pos.X, Y: pos.Y - 1}) {
+			if botFacingDir == botFacingLeft {
+				turnDirection = dirRight
+			} else if botFacingDir == botFacingRight {
+				turnDirection = dirLeft
+			}
+		} else if u.ArrayContains(adj, u.Vec2i{X: pos.X, Y: pos.Y + 1}) {
+			if botFacingDir == botFacingLeft {
+				turnDirection = dirLeft
+			} else if botFacingDir == botFacingRight {
+				turnDirection = dirRight
+			}
+		}
+	}
+
+	dirAscii := "L"
+	if turnDirection == dirRight {
+		dirAscii = "R"
+	}
+
+	return turnDirection, dirAscii
+}
+
+func buildInstructionString(instructions []string) string {
+	workingInstructions := make([]string, len(instructions))
+	copy(workingInstructions, instructions)
+
+	minimumRecurrence := 3
+	initialInstructionSubsetLen := 4
+
+	instructionStr := strings.Join(workingInstructions, ",")
+	progs := make([][]string, 3)
+	for i := range progs {
+		numFound := minimumRecurrence
+		subLen := initialInstructionSubsetLen
+		for numFound >= minimumRecurrence {
+			numFound = 1
+			instructionSubset := strings.Join(workingInstructions[0:subLen], ",")
+			if len(instructionSubset) > maxInstructionSetLength {
+				break
+			}
+			for x := len(instructionSubset); x <= len(instructionStr)-len(instructionSubset); x++ {
+				if instructionStr[x:x+len(instructionSubset)] == instructionSubset {
+					numFound++
+					x += len(instructionSubset)
+				}
+			}
+			if numFound >= minimumRecurrence {
+				subLen += 2
+			}
+		}
+		if numFound < minimumRecurrence {
+			subLen -= 2
+		}
+		progs[i] = make([]string, subLen)
+		copy(progs[i], workingInstructions[0:subLen])
+
+		instructionStr = strings.ReplaceAll(instructionStr, strings.Join(progs[i], ","), "")
+		instructionStr = strings.TrimPrefix(strings.ReplaceAll(instructionStr, ",,", ","), ",")
+
+		if len(instructionStr) == 0 {
+			workingInstructions = nil
+		} else {
+			workingInstructions = strings.Split(instructionStr, ",")
+		}
+	}
+
+	if workingInstructions != nil {
+		panic("failed to use up all instructions")
+	}
+
+	programStr := strings.Join(instructions, ",")
+	for i := range progs {
+		programStr = strings.ReplaceAll(programStr, strings.Join(progs[i], ","), fmt.Sprintf("%c", 'A'+i))
+	}
+
+	sb := strings.Builder{}
+	sb.WriteString(programStr)
+	sb.WriteRune('\n')
+
+	for i := range progs {
+		sb.WriteString(strings.Join(progs[i], ","))
+		sb.WriteRune('\n')
+	}
+
+	runDebug := 'n'
+	sb.WriteRune(runDebug)
+	sb.WriteRune('\n')
+
+	return sb.String()
+}
+
+func (grid day17Grid) solvePath(botLocation u.Vec2i, botFacingDir botFacing) string {
+	instructions := make([]string, 0)
+
+	pos := botLocation
+	endLocation := grid.findEndLocation(botLocation)
+	for {
+		if pos == endLocation {
+			break
+		}
+
+		turnDirection, dirAscii := grid.getTurnDirectionFromCorner(pos, botFacingDir)
+		if turnDirection == 0 {
+			panic("at an invalid location somehow")
+		}
+
+		instructions = append(instructions, dirAscii)
+
+		botFacingDir = botFacingDir.getNewFacingDir(turnDirection)
+		numMoved := 0
+		for {
+			cell, newY, newX := grid.getCellTypeInDirection(pos.Y, pos.X, botFacingDir)
+			if cell != cellTypeScaffold {
+				break
+			}
+			pos.X = newX
+			pos.Y = newY
+			numMoved++
+		}
+		instructions = append(instructions, fmt.Sprintf("%d", numMoved))
+	}
+
+	return buildInstructionString(instructions)
+}
+
+func (d *Day17) Part1() string {
+	grid := day17Grid{}
+	y := 0
+	var botLocation u.Vec2i
+	var botFacingDir botFacing
+
+	d.program.RunIn(func(inputStep int) int64 {
+		return 0
+	}, func(val int64, state u.IntcodeProgramState) {
+		rVal := rune(val)
+		y, botLocation, botFacingDir = grid.processGridUpdate(y, rVal, botLocation, botFacingDir)
+	})
+
+	alignmentParameterTotal := 0
+	grid.forEachCellOfType(cellTypeScaffold, func(y, x int) {
+		if numSurrounding := len(grid.getAdjacentScaffolds(y, x)); numSurrounding == 4 {
+			alignmentParameterTotal += y * x
+		}
+	})
+
+	// endLocation := grid.findEndLocation(botLocation)
+	// grid.Draw(botLocation, botFacingDir, endLocation)
+
+	return fmt.Sprintf("Alignment parameter sum: %s%d%s", u.TextBold, alignmentParameterTotal, u.TextReset)
+}
+
+func (d *Day17) Part2() string {
+	beforeGrid := day17Grid{}
+	var beforeBotLocation u.Vec2i
+	var beforeBotFacing botFacing
+
+	afterGrid := day17Grid{}
+	var afterBotLocation u.Vec2i
+	var afterBotFacing botFacing
+
+	d.program.Reset()
+	d.program.SetMemory(0, 2)
+
+	row := 0
+	var outputState int
+	var lastOutput int64
+	var instructionStr string
+	d.program.RunIn(func(inputStep int) int64 {
+		return int64(instructionStr[inputStep-1])
+	}, func(val int64, state u.IntcodeProgramState) {
+		rVal := rune(val)
+		if outputState == 0 {
+			row, beforeBotLocation, beforeBotFacing = beforeGrid.processGridUpdate(row, rVal, beforeBotLocation, beforeBotFacing)
+		} else if outputState == 2 {
+			row, afterBotLocation, afterBotFacing = afterGrid.processGridUpdate(row, rVal, afterBotLocation, afterBotFacing)
+		}
+
+		if rVal == '\n' && lastOutput == '\n' {
+			if outputState == 0 {
+				instructionStr = beforeGrid.solvePath(beforeBotLocation, beforeBotFacing)
+			}
+			outputState++
+			row = 0
+		}
+
+		lastOutput = val
+	})
+
+	// fmt.Println("initial grid:")
+	// beforeEndLocation := beforeGrid.findEndLocation(beforeBotLocation)
+	// beforeGrid.Draw(beforeBotLocation, beforeBotFacing, beforeEndLocation)
+
+	// fmt.Println("completed grid:")
+	// afterEndLocation := afterGrid.findEndLocation(afterBotLocation)
+	// afterGrid.Draw(afterBotLocation, afterBotFacing, afterEndLocation)
+
+	return fmt.Sprintf("Dust collected after traveling all paths: %s%d%s", u.TextBold, lastOutput, u.TextReset)
+}
--- a/days/18.go
+++ b/days/18.go
@ -0,0 +1,345 @@
+package days
+
+import (
+	"container/heap"
+	"fmt"
+	"math"
+	"strings"
+
+	u "parnic.com/aoc2019/utilities"
+)
+
+type day18Cell int
+type day18Vec u.Vec2[int]
+type day18Graph map[rune][]u.Pair[rune, int]
+
+const (
+	day18CellWall day18Cell = iota
+	day18CellOpen
+)
+
+var (
+	day18AdjacentOffsets = []day18Vec{
+		{X: -1, Y: 0},
+		{X: 1, Y: 0},
+		{X: 0, Y: -1},
+		{X: 0, Y: 1},
+	}
+)
+
+type reachableKeysMemo struct {
+	pos       rune
+	keysFound int
+}
+
+type minStepsMemo struct {
+	pos        string
+	keysToFind int
+	keysFound  int
+}
+
+type Day18 struct {
+	entrance           day18Vec
+	grid               [][]day18Cell
+	doors              map[day18Vec]int
+	keys               map[day18Vec]int
+	knownReachableKeys map[reachableKeysMemo][]u.Pair[rune, int]
+	knownMinimumSteps  map[minStepsMemo]int
+}
+
+func (d *Day18) Parse() {
+	d.doors = make(map[day18Vec]int)
+	d.keys = make(map[day18Vec]int)
+	d.knownReachableKeys = make(map[reachableKeysMemo][]u.Pair[rune, int])
+	d.knownMinimumSteps = make(map[minStepsMemo]int, 0)
+
+	lines := u.GetStringLines("18p")
+	d.grid = make([][]day18Cell, len(lines))
+	for i, line := range lines {
+		d.grid[i] = make([]day18Cell, len(line))
+		for j, char := range line {
+			if char == '#' {
+				d.grid[i][j] = day18CellWall
+			} else if char == '.' {
+				d.grid[i][j] = day18CellOpen
+			} else if char == '@' {
+				d.grid[i][j] = day18CellOpen
+				d.entrance = day18Vec{X: j, Y: i}
+			} else if char >= 'A' && char <= 'Z' {
+				d.grid[i][j] = day18CellOpen
+				d.doors[day18Vec{X: j, Y: i}] = int(char - 'A')
+			} else if char >= 'a' && char <= 'z' {
+				d.grid[i][j] = day18CellOpen
+				d.keys[day18Vec{X: j, Y: i}] = int(char - 'a')
+			}
+		}
+	}
+}
+
+func (d Day18) Num() int {
+	return 18
+}
+
+func (d Day18) Draw(grid [][]day18Cell, keys, doors map[day18Vec]int, entrances ...day18Vec) {
+	for y := range grid {
+		for x := range grid[y] {
+			switch grid[y][x] {
+			case day18CellWall:
+				fmt.Print("█")
+			case day18CellOpen:
+				posVec := day18Vec{X: x, Y: y}
+				if _, exists := doors[posVec]; exists {
+					fmt.Printf("%c", rune(doors[posVec]+'A'))
+				} else if _, exists := keys[posVec]; exists {
+					fmt.Printf("%c", rune(keys[posVec]+'a'))
+				} else if u.ArrayContains(entrances, posVec) {
+					fmt.Print("@")
+				} else {
+					fmt.Print(".")
+				}
+			}
+		}
+		fmt.Println()
+	}
+}
+
+func (d Day18) findAdjacentCells(inPos day18Vec, keys, doors map[day18Vec]int, grid [][]day18Cell) []u.Pair[rune, int] {
+	found := make([]u.Pair[rune, int], 0)
+
+	getAdjacent := func(pos day18Vec) []day18Vec {
+		retAdjacent := make([]day18Vec, 0, len(day18AdjacentOffsets))
+		for _, off := range day18AdjacentOffsets {
+			offVec := day18Vec{X: pos.X + off.X, Y: pos.Y + off.Y}
+			if grid[offVec.Y][offVec.X] == day18CellWall {
+				continue
+			}
+			retAdjacent = append(retAdjacent, offVec)
+		}
+
+		return retAdjacent
+	}
+
+	queue := make([]u.Pair[int, day18Vec], 0)
+	visited := make(map[day18Vec]bool)
+	for _, adjacent := range getAdjacent(inPos) {
+		queue = append(queue, u.Pair[int, day18Vec]{First: 1, Second: adjacent})
+	}
+
+	for len(queue) > 0 {
+		next := queue[0]
+		queue = queue[1:]
+
+		if _, exists := visited[next.Second]; !exists {
+			visited[next.Second] = true
+
+			key, adjacentIsKey := keys[next.Second]
+			door, adjacentIsDoor := doors[next.Second]
+			if adjacentIsKey || adjacentIsDoor {
+				var rVal rune
+				if adjacentIsKey {
+					rVal = rune('a' + key)
+				} else if adjacentIsDoor {
+					rVal = rune('A' + door)
+				}
+
+				alreadyFound := false
+				for _, p := range found {
+					if p.First == rVal {
+						alreadyFound = true
+						break
+					}
+				}
+				if !alreadyFound {
+					found = append(found, u.Pair[rune, int]{First: rVal, Second: next.First})
+					continue
+				}
+			}
+
+			for _, neighbor := range getAdjacent(next.Second) {
+				if _, exists := visited[neighbor]; !exists {
+					queue = append(queue, u.Pair[int, day18Vec]{First: next.First + 1, Second: neighbor})
+				}
+			}
+		}
+	}
+
+	return found
+}
+
+type day18PriorityQueue struct {
+	distance int
+	neighbor rune
+}
+type day18PriorityQueueHeap []day18PriorityQueue
+
+func (h day18PriorityQueueHeap) Len() int           { return len(h) }
+func (h day18PriorityQueueHeap) Less(i, j int) bool { return h[i].distance < h[j].distance }
+func (h day18PriorityQueueHeap) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }
+
+func (h *day18PriorityQueueHeap) Push(x any) {
+	*h = append(*h, x.(day18PriorityQueue))
+}
+
+func (h *day18PriorityQueueHeap) Pop() any {
+	old := *h
+	n := len(old)
+	x := old[n-1]
+	*h = old[0 : n-1]
+	return x
+}
+
+func (d Day18) reachableKeys(inPos rune, keysFound int, graph day18Graph) []u.Pair[rune, int] {
+	memo := reachableKeysMemo{
+		pos:       inPos,
+		keysFound: keysFound,
+	}
+	if v, exists := d.knownReachableKeys[memo]; exists {
+		return v
+	}
+
+	ret := make([]u.Pair[rune, int], 0)
+	distance := make(map[rune]int)
+
+	ih := make(day18PriorityQueueHeap, 0)
+
+	for _, p := range graph[inPos] {
+		ih = append(ih, day18PriorityQueue{
+			distance: p.Second,
+			neighbor: p.First,
+		})
+	}
+
+	heap.Init(&ih)
+
+	for ih.Len() > 0 {
+		node := heap.Pop(&ih).(day18PriorityQueue)
+
+		// it's a key and we haven't picked it up yet...
+		if node.neighbor >= 'a' && node.neighbor <= 'z' && (1<<int(node.neighbor-'a')&keysFound) == 0 {
+			ret = append(ret, u.Pair[rune, int]{First: node.neighbor, Second: node.distance})
+			continue
+		}
+
+		// it's a door but we don't have the key yet...
+		if node.neighbor >= 'A' && node.neighbor <= 'Z' && ((1<<int(node.neighbor-'A'))&keysFound) == 0 {
+			continue
+		}
+
+		for _, p := range graph[node.neighbor] {
+			newDistance := node.distance + p.Second
+			if dist, exists := distance[p.First]; !exists || newDistance < dist {
+				distance[p.First] = newDistance
+				heap.Push(&ih, day18PriorityQueue{
+					distance: newDistance,
+					neighbor: p.First,
+				})
+			}
+		}
+	}
+
+	d.knownReachableKeys[memo] = ret
+	return ret
+}
+
+func (d Day18) minimumSteps(inPos string, keysToFind int, keysFound int, graph day18Graph) int {
+	memo := minStepsMemo{
+		pos:        inPos,
+		keysToFind: keysToFind,
+		keysFound:  keysFound,
+	}
+	if v, exists := d.knownMinimumSteps[memo]; exists {
+		return v
+	}
+
+	if keysToFind == 0 {
+		return 0
+	}
+
+	best := math.Inf(1)
+	for _, item := range inPos {
+		for _, p := range d.reachableKeys(item, keysFound, graph) {
+			sb := strings.Builder{}
+			oldIdx := strings.IndexRune(inPos, item)
+			for i := range inPos {
+				if i == oldIdx {
+					sb.WriteRune(p.First)
+				} else {
+					sb.WriteByte(inPos[i])
+				}
+			}
+			newKeys := keysFound + (1 << (p.First - 'a'))
+			dist := p.Second
+
+			dist += d.minimumSteps(sb.String(), keysToFind-1, newKeys, graph)
+
+			if float64(dist) < best {
+				best = float64(dist)
+			}
+		}
+	}
+
+	d.knownMinimumSteps[memo] = int(best)
+	return int(best)
+}
+
+func (d Day18) buildGraph(pos []day18Vec, keys map[day18Vec]int, doors map[day18Vec]int, grid [][]day18Cell) day18Graph {
+	graph := make(day18Graph)
+	for i, p := range pos {
+		adjacent := d.findAdjacentCells(p, keys, doors, grid)
+		graph[rune('1'+i)] = adjacent
+	}
+	for keyPos, keyType := range keys {
+		graph[rune('a'+keyType)] = d.findAdjacentCells(keyPos, keys, doors, grid)
+	}
+	for doorPos, doorType := range doors {
+		graph[rune('A'+doorType)] = d.findAdjacentCells(doorPos, keys, doors, grid)
+	}
+
+	return graph
+}
+
+func (d Day18) part2PatchMap(grid [][]day18Cell, entrance day18Vec) []day18Vec {
+	grid[entrance.Y-1][entrance.X] = day18CellWall
+	grid[entrance.Y][entrance.X-1] = day18CellWall
+	grid[entrance.Y][entrance.X] = day18CellWall
+	grid[entrance.Y][entrance.X+1] = day18CellWall
+	grid[entrance.Y+1][entrance.X] = day18CellWall
+
+	return []day18Vec{
+		{X: entrance.X - 1, Y: entrance.Y - 1},
+		{X: entrance.X + 1, Y: entrance.Y - 1},
+		{X: entrance.X - 1, Y: entrance.Y + 1},
+		{X: entrance.X + 1, Y: entrance.Y + 1},
+	}
+}
+
+func (d *Day18) Part1() string {
+	// fmt.Println("initial state:")
+	// d.Draw(d.grid, d.keys, d.doors, d.entrance)
+
+	graph := d.buildGraph([]day18Vec{d.entrance}, d.keys, d.doors, d.grid)
+	minSteps := d.minimumSteps("1", len(d.keys), 0, graph)
+
+	return fmt.Sprintf("Total distance traveled: %s%d%s", u.TextBold, minSteps, u.TextReset)
+}
+
+func (d *Day18) Part2() string {
+	// fmt.Println("initial state:")
+	grid := make([][]day18Cell, len(d.grid))
+	for i := range d.grid {
+		grid[i] = make([]day18Cell, len(d.grid[i]))
+		copy(grid[i], d.grid[i])
+	}
+
+	entrances := d.part2PatchMap(grid, d.entrance)
+	// d.Draw(grid, d.keys, d.doors, entrances...)
+
+	// clear memoized maps that (might have) came from part1
+	d.knownMinimumSteps = make(map[minStepsMemo]int)
+	d.knownReachableKeys = make(map[reachableKeysMemo][]u.Pair[rune, int])
+
+	graph := d.buildGraph(entrances, d.keys, d.doors, grid)
+	minSteps := d.minimumSteps("1234", len(d.keys), 0, graph)
+
+	return fmt.Sprintf("Total distance traveled: %s%d%s", u.TextBold, minSteps, u.TextReset)
+}
--- a/days/19.go
+++ b/days/19.go
@ -0,0 +1,146 @@
+package days
+
+import (
+	"fmt"
+
+	u "parnic.com/aoc2019/utilities"
+)
+
+type Day19 struct {
+	program u.IntcodeProgram
+}
+
+func (d *Day19) Parse() {
+	d.program = u.LoadIntcodeProgram("19p")
+}
+
+func (d Day19) Num() int {
+	return 19
+}
+
+func (d *Day19) Part1() string {
+	grid := make([][]bool, 50)
+	for y := 0; y < len(grid); y++ {
+		grid[y] = make([]bool, 50)
+	}
+
+	count := int64(0)
+
+	for y := 0; y < 50; y++ {
+		for x := 0; x < 50; x++ {
+			d.program.Reset()
+			d.program.RunIn(func(inputStep int) int64 {
+				if inputStep == 1 {
+					return int64(x)
+				}
+
+				return int64(y)
+			}, func(val int64, state u.IntcodeProgramState) {
+				res := val == 1
+				grid[y][x] = res
+				if res {
+					count++
+				}
+			})
+		}
+	}
+
+	// fmt.Println("50x50 tractor view:")
+	// for y := 0; y < len(grid); y++ {
+	// 	for x := 0; x < len(grid[y]); x++ {
+	// 		if grid[y][x] {
+	// 			fmt.Print("█")
+	// 		} else {
+	// 			fmt.Print(" ")
+	// 		}
+	// 	}
+	// 	fmt.Println()
+	// }
+
+	return fmt.Sprintf("Points affected in 50x50 area: %s%d%s", u.TextBold, count, u.TextReset)
+}
+
+func (d *Day19) Part2() string {
+	f := func(x, y int) bool {
+		ret := false
+		d.program.Reset()
+		d.program.RunIn(func(inputStep int) int64 {
+			if inputStep == 1 {
+				return int64(x)
+			}
+			return int64(y)
+		}, func(val int64, state u.IntcodeProgramState) {
+			ret = val == 1
+		})
+
+		return ret
+	}
+
+	// find lower bound
+	// this may not be necessary, but helps seed the bisect with a known-good lower bound
+	startY := 0
+	startX := 0
+	for y := 1; startY == 0; y++ {
+		for x := 0; x < 10*y; x++ {
+			if f(x, y) {
+				startY = y
+				startX = x
+				break
+			}
+		}
+	}
+
+	lastGoodX := 0
+	threshold := 1
+	// add 100 to start y since we know it has to be a 100x100 square.
+	// since we multiply x by 10,000 for the final result, that tells us y cannot be 10k+
+	y := u.Bisect(startY+100, 9999, threshold, func(y int) bool {
+		foundX := false
+		for x := startX; ; x++ {
+			// check top left
+			if !f(x, y) {
+				if !foundX {
+					continue
+				} else {
+					return true
+				}
+			}
+			if !foundX {
+				foundX = true
+			}
+
+			// check top right
+			if !f(x+99, y) {
+				return true
+			}
+			// check bottom left
+			if !f(x, y+99) {
+				continue
+			}
+
+			// we believe the corners work, so run final validations on the full borders.
+			// this may not be necessary, but i've seen some rows end up shorter than a
+			// previous row because of the angle of the beam and our integer fidelity.
+			// plus it's really not that much more expensive to do to be certain we're correct.
+			for y2 := y; y2 < y+100; y2++ {
+				// right wall
+				if !f(x+99, y2) {
+					return true
+				}
+				// left wall
+				if !f(x, y2) {
+					return true
+				}
+			}
+
+			lastGoodX = x
+			return false
+		}
+	})
+
+	// since we invert our bisect success returns, we need to increment y to
+	// tip back over into the "success" range
+	y += threshold
+	result := (lastGoodX * 10000) + y
+	return fmt.Sprintf("Closest 100x100 square for the ship starts at %d,%d = %s%d%s", lastGoodX, y, u.TextBold, result, u.TextReset)
+}
--- a/days/20.go
+++ b/days/20.go
@ -0,0 +1,398 @@
+package days
+
+import (
+	"container/heap"
+	"fmt"
+	"math"
+	"strings"
+
+	u "parnic.com/aoc2019/utilities"
+)
+
+type day20Cell int8
+type day20Graph map[day20Portal][]u.Pair[day20Portal, int]
+
+const (
+	day20CellWall day20Cell = iota
+	day20CellPath
+	day20CellDonutHole
+)
+
+var (
+	day20AdjacentOffsets = []u.Vec2i{
+		{X: -1, Y: 0},
+		{X: 1, Y: 0},
+		{X: 0, Y: -1},
+		{X: 0, Y: 1},
+	}
+
+	entrancePortal = day20Portal{name: "AA"}
+	exitPortal     = day20Portal{name: "ZZ"}
+)
+
+type day20Portal struct {
+	name  string
+	inner bool
+	depth int
+}
+
+type Day20 struct {
+	grid        [][]day20Cell
+	entrance    u.Vec2i
+	exit        u.Vec2i
+	portals     map[day20Portal]u.Vec2i
+	portalNames []string
+}
+
+func (d *Day20) Parse() {
+	d.portals = make(map[day20Portal]u.Vec2i)
+	d.portalNames = make([]string, 0)
+
+	lines := u.GetStringLines("20p")
+	d.grid = make([][]day20Cell, len(lines)-4)
+	currPortal := strings.Builder{}
+
+	for row, line := range lines {
+		y := row - 2
+		isGridRow := row >= 2 && row < len(lines)-2
+
+		if isGridRow {
+			d.grid[y] = make([]day20Cell, len(line)-4)
+		}
+
+		for col, ch := range lines[row] {
+			x := col - 2
+			isGridCol := col >= 2 && col < len(line)-2
+
+			if isGridRow && isGridCol {
+				if ch == '#' {
+					d.grid[y][x] = day20CellWall
+				} else if ch == '.' {
+					d.grid[y][x] = day20CellPath
+				} else {
+					d.grid[y][x] = day20CellDonutHole
+				}
+			}
+
+			if ch >= 'A' && ch <= 'Z' {
+				portalX := 0
+				portalY := 0
+				if len(line) > col+1 && line[col+1] >= 'A' && line[col+1] <= 'Z' {
+					currPortal.WriteRune(ch)
+					currPortal.WriteRune(rune(line[col+1]))
+
+					if len(line) > col+2 && line[col+2] == '.' {
+						portalY = y
+						portalX = x + 2
+					} else if col-1 >= 0 && line[col-1] == '.' {
+						portalY = y
+						portalX = x - 1
+					} else {
+						panic("!")
+					}
+				} else if len(lines) > row+1 && lines[row+1][col] >= 'A' && lines[row+1][col] <= 'Z' {
+					currPortal.WriteRune(ch)
+					currPortal.WriteRune(rune(lines[row+1][col]))
+
+					if len(lines) > row+2 && lines[row+2][col] == '.' {
+						portalY = y + 2
+						portalX = x
+					} else if row-1 >= 0 && lines[row-1][col] == '.' {
+						portalY = y - 1
+						portalX = x
+					} else {
+						panic("!")
+					}
+				}
+
+				if currPortal.Len() == 2 {
+					portalName := currPortal.String()
+					portalVec := u.Vec2i{X: portalX, Y: portalY}
+
+					if portalName == entrancePortal.name {
+						d.entrance = portalVec
+					} else if portalName == exitPortal.name {
+						d.exit = portalVec
+					} else {
+						portal := day20Portal{
+							name:  portalName,
+							inner: !d.isOuterPortal(portalVec),
+						}
+						d.portals[portal] = portalVec
+
+						u.AddToArray(&d.portalNames, portalName)
+					}
+
+					currPortal.Reset()
+				}
+			}
+		}
+	}
+}
+
+func (d Day20) Num() int {
+	return 20
+}
+
+func (d Day20) isPortal(vec u.Vec2i) (bool, int) {
+	if d.grid[vec.Y][vec.X] != day20CellPath {
+		return false, 0
+	}
+
+	for i, name := range d.portalNames {
+		p, exists := d.portals[day20Portal{name: name, inner: !d.isOuterPortal(vec)}]
+		if exists && vec == p {
+			return true, i
+		}
+	}
+
+	return false, 0
+}
+
+func (d Day20) Draw() {
+	for y := range d.grid {
+		for x := range d.grid[y] {
+			switch d.grid[y][x] {
+			case day20CellWall:
+				fmt.Print("█")
+			case day20CellDonutHole:
+				fmt.Print(" ")
+			case day20CellPath:
+				posVec := u.Vec2i{X: x, Y: y}
+				if posVec == d.entrance {
+					fmt.Print("@")
+				} else if posVec == d.exit {
+					fmt.Print("!")
+				} else {
+					isPortal, portalIdx := d.isPortal(posVec)
+					if isPortal {
+						ch := 'a' + portalIdx
+						if ch > 'z' {
+							ch = 'A' + (portalIdx - 26)
+						}
+						fmt.Printf("%c", ch)
+					} else {
+						fmt.Print(" ")
+					}
+				}
+			}
+		}
+
+		fmt.Println()
+	}
+}
+
+func (d Day20) isOuterPortal(pos u.Vec2i) bool {
+	return pos.X == 0 || pos.Y == 0 || pos.X == len(d.grid[0])-1 || pos.Y == len(d.grid)-1
+}
+
+func (d Day20) findAdjacentCells(inPos u.Vec2i) []u.Pair[day20Portal, int] {
+	found := make([]u.Pair[day20Portal, int], 0)
+
+	getAdjacent := func(pos u.Vec2i) []u.Vec2i {
+		retAdjacent := make([]u.Vec2i, 0, len(day20AdjacentOffsets))
+		for _, off := range day20AdjacentOffsets {
+			offVec := u.Vec2i{X: pos.X + off.X, Y: pos.Y + off.Y}
+			if offVec.Y < 0 || offVec.Y >= len(d.grid) || offVec.X < 0 || offVec.X >= len(d.grid[0]) {
+				continue
+			}
+			if d.grid[offVec.Y][offVec.X] != day20CellPath {
+				continue
+			}
+			retAdjacent = append(retAdjacent, offVec)
+		}
+
+		return retAdjacent
+	}
+
+	queue := make([]u.Pair[int, u.Vec2i], 0)
+	visited := map[u.Vec2i]bool{
+		inPos: true,
+	}
+	for _, adjacent := range getAdjacent(inPos) {
+		queue = append(queue, u.Pair[int, u.Vec2i]{First: 1, Second: adjacent})
+	}
+
+	for len(queue) > 0 {
+		next := queue[0]
+		queue = queue[1:]
+
+		if _, exists := visited[next.Second]; !exists {
+			visited[next.Second] = true
+
+			adjacentIsPortal, portalIdx := d.isPortal(next.Second)
+			if adjacentIsPortal || next.Second == d.entrance || next.Second == d.exit {
+				var portalName string
+				if next.Second == d.entrance {
+					portalName = entrancePortal.name
+				} else if next.Second == d.exit {
+					portalName = exitPortal.name
+				} else {
+					portalName = d.portalNames[portalIdx]
+				}
+
+				alreadyFound := false
+				for _, p := range found {
+					if p.First.name == portalName {
+						alreadyFound = true
+						break
+					}
+				}
+				if !alreadyFound {
+					found = append(found, u.Pair[day20Portal, int]{First: day20Portal{
+						name:  portalName,
+						inner: !d.isOuterPortal(next.Second),
+					}, Second: next.First})
+					continue
+				}
+			}
+
+			for _, neighbor := range getAdjacent(next.Second) {
+				if _, exists := visited[neighbor]; !exists {
+					queue = append(queue, u.Pair[int, u.Vec2i]{First: next.First + 1, Second: neighbor})
+				}
+			}
+		}
+	}
+
+	return found
+}
+
+type day20PriorityQueue struct {
+	distance int
+	neighbor day20Portal
+}
+type day20PriorityQueueHeap []day20PriorityQueue
+
+func (h day20PriorityQueueHeap) Len() int           { return len(h) }
+func (h day20PriorityQueueHeap) Less(i, j int) bool { return h[i].distance < h[j].distance }
+func (h day20PriorityQueueHeap) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }
+
+func (h *day20PriorityQueueHeap) Push(x any) {
+	*h = append(*h, x.(day20PriorityQueue))
+}
+
+func (h *day20PriorityQueueHeap) Pop() any {
+	old := *h
+	n := len(old)
+	x := old[n-1]
+	*h = old[0 : n-1]
+	return x
+}
+
+func (d Day20) dijkstra(graph day20Graph, start, end day20Portal, neighborFunc func(inPortal day20Portal) []u.Pair[day20Portal, int]) int {
+	distance := make(map[day20Portal]int)
+
+	ih := day20PriorityQueueHeap{
+		day20PriorityQueue{
+			distance: 0,
+			neighbor: start,
+		},
+	}
+
+	heap.Init(&ih)
+	visited := make(map[day20Portal]bool)
+
+	for ih.Len() > 0 {
+		node := heap.Pop(&ih).(day20PriorityQueue)
+
+		if node.neighbor == end {
+			return node.distance
+		}
+
+		if _, exists := visited[node.neighbor]; exists {
+			continue
+		}
+
+		visited[node.neighbor] = true
+
+		for _, p := range neighborFunc(node.neighbor) {
+			if _, exists := visited[p.First]; exists {
+				continue
+			}
+
+			newDistance := node.distance + p.Second
+			if dist, exists := distance[p.First]; !exists || newDistance < dist {
+				distance[p.First] = newDistance
+				heap.Push(&ih, day20PriorityQueue{
+					distance: newDistance,
+					neighbor: p.First,
+				})
+			}
+		}
+	}
+
+	return math.MaxInt
+}
+
+func (d Day20) buildGraph() day20Graph {
+	graph := make(day20Graph, len(d.portals)+1)
+
+	adjacent := d.findAdjacentCells(d.entrance)
+	graph[entrancePortal] = adjacent
+
+	for portal, portalVec := range d.portals {
+		adjacent = d.findAdjacentCells(portalVec)
+		graph[portal] = adjacent
+	}
+
+	return graph
+}
+
+func (d Day20) getDepthNeighbors(graph day20Graph, portal day20Portal) []u.Pair[day20Portal, int] {
+	basePortal := portal
+	basePortal.depth = 0
+	baseNeighbors := graph[basePortal]
+
+	neighbors := make([]u.Pair[day20Portal, int], 0)
+
+	if portal.inner {
+		n := day20Portal{name: portal.name, inner: false, depth: portal.depth + 1}
+		neighbors = append(neighbors, u.Pair[day20Portal, int]{First: n, Second: 1})
+	}
+
+	if portal.depth == 0 {
+		for _, i := range baseNeighbors {
+			if i.First.inner || i.First.name == entrancePortal.name || i.First.name == exitPortal.name {
+				neighbors = append(neighbors, u.Pair[day20Portal, int]{First: i.First, Second: i.Second})
+			}
+		}
+	} else {
+		if !portal.inner {
+			n := day20Portal{name: portal.name, inner: true, depth: portal.depth - 1}
+			neighbors = append(neighbors, u.Pair[day20Portal, int]{First: n, Second: 1})
+		}
+
+		for _, i := range baseNeighbors {
+			if i.First.name != entrancePortal.name && i.First.name != exitPortal.name {
+				n := day20Portal{name: i.First.name, inner: i.First.inner, depth: portal.depth}
+				neighbors = append(neighbors, u.Pair[day20Portal, int]{First: n, Second: i.Second})
+			}
+		}
+	}
+
+	return neighbors
+}
+
+func (d *Day20) Part1() string {
+	// d.Draw()
+
+	graph := d.buildGraph()
+
+	for portal, adjacent := range graph {
+		if portal.name == entrancePortal.name {
+			continue
+		}
+
+		graph[portal] = append(adjacent, u.Pair[day20Portal, int]{First: day20Portal{name: portal.name, inner: !portal.inner}, Second: 1})
+	}
+
+	distance := d.dijkstra(graph, entrancePortal, exitPortal, func(inPortal day20Portal) []u.Pair[day20Portal, int] { return graph[inPortal] })
+	return fmt.Sprintf("Steps to traverse maze: %s%d%s", u.TextBold, distance, u.TextReset)
+}
+
+func (d *Day20) Part2() string {
+	graph := d.buildGraph()
+	distance := d.dijkstra(graph, entrancePortal, exitPortal, func(inPortal day20Portal) []u.Pair[day20Portal, int] { return d.getDepthNeighbors(graph, inPortal) })
+	return fmt.Sprintf("Steps to traverse recursive maze: %s%d%s", u.TextBold, distance, u.TextReset)
+}
--- a/inputs/17p.txt
+++ b/inputs/17p.txt
@ -0,0 +1 @@
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--- a/inputs/18p.txt
+++ b/inputs/18p.txt
@ -0,0 +1,81 @@
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--- a/inputs/18s1.txt
+++ b/inputs/18s1.txt
@ -0,0 +1,3 @@
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--- a/inputs/18s2.txt
+++ b/inputs/18s2.txt
@ -0,0 +1,5 @@
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--- a/inputs/18s3.txt
+++ b/inputs/18s3.txt
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+++ b/inputs/18s4.txt
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+++ b/inputs/18s5.txt
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+++ b/inputs/18s6.txt
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+++ b/inputs/18s7.txt
@ -0,0 +1,7 @@
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+++ b/inputs/18s8.txt
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+++ b/inputs/19p.txt
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--- a/inputs/20p.txt
+++ b/inputs/20p.txt
@ -0,0 +1,125 @@
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+                                         G       V   M           I   O R       C                                           
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+  #.#####.#####.###.#####.###.#.#######.#.#.###.#.#####.###.#.#.#.#########.#.#.#####.#.###.#######.#.#######.#.###.###.#  
+  #...#...#.....#...#.#...#.#.#...#.#.....#.#.......#...#.#.#...#.#.#.......#.#.#...............#.#.#.........#.#.#.....#  
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+  #.#.........#.....#.#.#.#.#.......#.......#.#.#.......#.#...#.#...#...#...#.....#.#.#...#.#.....#.#.............#.#...#  
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+  #.#.#######.#.#######.###.#.#####.#######.#.#####.#.#.###.###.#####.#######.#.###.#######.#.#.#.#.#.#####.###.#.###.###  
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+  #.....#.#.#.#...#.#.#.#.#.#...#      F         O         O X         N U       W        #.#.....#.#.#...#.#.#.........#  
+  #.#####.#.#.#.###.#.#.#.#.#.###      Z         G         D L         B Y       W        ###.#####.#.###.#.#.###.###.###  
+  #...#.#.#.#.#.#...#.......#...#                                                         #.......#.....#...#...#.#.#...#  
+  #.###.#.#.#.#.###.#.#.###.#.#.#                                                         #.#.#######.###.#.###.#.#.#.###  
+PL....#.#.#...#...#...#...#...#.#                                                         #.#.#.#.#...#.#.#.....#.#.#.#.#  
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+YP..#.........#.#...#.#.#.#.....#                                                         #.#...#.....#.#.#.#.#...#...#.#  
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+EV..#.#...#.................#...#                                                       LV..#.#.....#...#...#.#.#...#.#..UN
+  #.###.#.#####.#.###.#.#.###.###                                                         #.#.#.###.###.#.#.#.#.#####.#.#  
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+  #...#...........#...#...#.#.#..XC                                                       #...#.#.#.........#...........#  
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+WV..#.#.#.#...............#.#.#.#                                                         #.#...#.#.#.#.#.......#.#.#....OD
+  #.#.#.#.#.#.#.###.#####.###.#.#                                                         #.###.#.#.#.#########.#########  
+  #.....#.#.#.#...#.#.....#.#.#..PI                                                       #.#.....#...#.....#.#.....#...#  
+  #####.###.#####.#.#####.#.#.#.#                                                         #.#.#.#.###.###.###.#########.#  
+AA........#.....#.#.#...#.......#                                                       UN..#.#.#.....#...#...#.#.#.#...#  
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+  #.#.#.#.#.#.#.#.#.###.#####.###                                                         #####.#.#.#.###.#.#.###.###.#.#  
+  #.#.#.#.#.#.....#.............#                                                         #.#...#...#.#.....#.#...#...#.#  
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+  #.#.#...#...#.#...#.....#.#.#.#                                                       SL....#.#.#.#.#.#.....#...#.#...#  
+  #.#.#.#.#.###.#.#.#######.#.#.#                                                         #####.#####.#.#.#.#####.#.#.###  
+EL..#...#.........#.........#.#..WV                                                       #...............#.#.#..........XP
+  #.###########.###.#########.###                                                         #.#########.###.###.###.#####.#  
+  #.#.......#...#...#...........#                                                         #.#.....#...#...#...#.......#.#  
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+UY..#...#.....#.#.........#.#....XP                                                     PL..#...#...#.#.#.#.#...#...#.#.#  
+  #.#.###.#.###########.#.#.#####                                                         #.###.#######.#.###.#.#.#####.#  
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+  #.#.#.#####.#.#.#.###.###.#####                                                         #.#.###############.#.#.###.#.#  
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+  ###############.###############                                                         #.#.###.#######.###########.###  
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+  #####.#.#.###.###.#######.###.#                                                         #########.#.#.###########.#.#.#  
+  #.....#.#.#.#.#.........#.#...#                                                         #.#.#.....#.#.#...#...#...#....TH
+  #.#####.###.#.#######.#####.###                                                         #.#.###.#.#.#########.###.#.#.#  
+ZZ....#...#...#.#...........#.#.#                                                       JG........#.#.................#.#  
+  ###.#.###.#.#.###.#.#.#####.#.#                                                         #.###.#.###.#.#.#####.###.#.###  
+JH....#.....#.......#.#...#......EV                                                       #.#...#...#.#.#...#.....#.#...#  
+  #.#.#######.#.#####.#.#####.###                                                         #.###.#########.###.#.#####.#.#  
+  #.#.#.......#.#.#.#.#.....#.#.#                                                         #.#...#...........#.#.#.#...#.#  
+  #.#.###.#.#.###.#.#.#######.#.#    V     J           Y       T     C     B       O      #.#####.###.#.###.#.###.###.#.#  
+  #.#.#...#.#...#.....#.#.......#    O     H           P       R     K     R       A      #.#.....#...#...#.#.#.#.....#.#  
+  #.#.#.#.###.#.#.#.#.#.#.###.#.#####.#####.###########.#######.#####.#####.#######.###############.#.#.#.###.#.#.#.#.###  
+  #.#.#.#.#...#.#.#.#...#...#.#.#.......#.......#...#.....#.....#.......#...#...#.........#.#.#.....#.#.#.#.#.#...#.#.#.#  
+  ###.#####.#.#######.###.###.#######.#####.#####.###.#######.###.#######.###.#.#.#.#.###.#.#.###.#####.###.#########.#.#  
+  #.....#.#.#.....#...#...#.#.#...........#.........#.....#...#.#.....#.#.....#.#.#.#.#.....#...#.#.#.........#.........#  
+  #.#####.#.###.#####.#####.#.#.###.###.#.###.#.###.#####.#.#.#.#.#####.###.###.#.#####.#.###.#####.###.###.###.#.#.###.#  
+  #...#...#...#.#.........#...#.#...#.#.#.#.#.#...#.#.....#.#...#.......#.#.#...#.#...#.#.#.....#.#.....#.....#.#.#.#...#  
+  #######.#####.#####.#######.#####.#.#.###.#####.#####.###.###########.#.#####.#.#.#########.###.###.#.###.#######.###.#  
+  #.......#.#.....#...#.........#...#.#.#...#.........#...#.#.#.......#...#.#.#.#...#...#...#.#.....#.#.#.#.#.........#.#  
+  #.#.#.#.#.#.#####.#####.###.#####.#.#.#.#####.#.#.#.###.#.#.#####.#.#.###.#.#.#.###.###.###.###.###.###.###.#.###.#####  
+  #.#.#.#.......#...#...#.#...#.......#.#...#...#.#.#.#.#.#.....#...#.#.....#...#...#.#.#.........#.#...#...#.#.#.......#  
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+  #...#.#.#.....#.#.#.#.........#.#.........#.....#.#...#.#.#.#.#.#.#.....#.#...#...#...#...#.#.....#.#.#.#.......#.#.#.#  
+  #.###.###.#.#####.#.#########.#.#######.#.###.#####.###.#.#.#####.###.#######.#.###.###.#######.#.#.#####.#.#.#.###.###  
+  #.....#...#...#.#.....#...............#.#.#.....#.......#.#.#.....#.#...#.....#.....#.....#.....#.....#.#.#.#.#.#.....#  
+  #####.#.#.###.#.#.#########.#####.###.#.###.###.#######.#.#####.###.#.#.#####.#.###.#.#.#######.#.#.###.#.#######.#.#.#  
+  #.......#.#.#.#.....#.......#.#...#.#.....#.#...#.#.#...#...#.......#.#.#.....#.#.....#...#...#.#.#.#.......#.#.#.#.#.#  
+  #.###.#.#.#.###.#######.#####.#.#.#####.#.###.###.#.#.#.#.#####.#####.#####.###.#.###.###.#.###.#.###########.#.#.#.#.#  
+  #.#.#.#.#...#...#...#.#.#.#.#.#.#.....#.#...#...#.....#.#...#.#.....#.#.......#.#.#...#.#.....#.#.#.........#...#.#.#.#  
+  #.#.#.#.#.###.#####.#.###.#.#.###.#######.#####.#.###.###.#.#.#.#############.#######.#.#.###.#####.#.###.###.#####.###  
+  #.#.#.#.#...#...#.#.....................#.#.....#...#.#...#...#.#...#.#.......#...#.#...#.#.#.#.....#.#.........#.#...#  
+  #.#.#.#.#.#######.#####.#####.#####.#########.#.#.#########.#.#.###.#.#####.###.###.#.#.###.#####.#########.#####.#####  
+  #.#...#.#.#...#.........#.#.#.#.......#...#.#.#.#.........#.#.#.#.....#...........#...#.#.......#.#.#.#.#...........#.#  
+  #.#######.###.###.#######.#.#####.#####.###.#.#######.#####.###.###.#.###.###.#######.#######.###.#.#.#.###.###.###.#.#  
+  #.....#.#.#.#.#.#.#.#.....#.........#.........#.#...#...#.#...#.....#.#.#...#.#.#.#.#.....#...............#...#.#.....#  
+  #.#####.###.#.#.###.#####.#######.#####.#.###.#.#.#.#.###.#.#########.#.#.###.#.#.#.#.#########.#####.#.#.#######.#.#.#  
+  #.#.#.......................#.#.#.#...#.#.#.....#.#...#.#...#.#.#.......#.#.....#.#...#...#.........#.#.#.......#.#.#.#  
+  #.#.#.###.#####.#########.#.#.#.#.#.###########.#.###.#.#.###.#.###.###.###.#####.###.###.#.#.#.#.###.#####.#.###.#####  
+  #.#...#.#.#.#...#.........#.........#...#.#.....#...#.#.......#...#...#.#.....#...#.........#.#.#...#...#...#.#.#...#.#  
+  #######.###.###.#####.#####.#####.#.#.###.###.###.#######.#.#.#.#####.#######.#.#.#.#####.#####.#.#.#.#####.###.#####.#  
+  #...............#.....#.......#...#.....#.......#.....#...#.#.#.......#.......#.#.......#.....#.#.#.#.....#...........#  
+  #####################################.#####.#######.#######.###.#########.#####.#######################################  
+                                       O     C       N       X   F         S     W                                         
+                                       G     K       B       L   Z         L     W                                         
--- a/inputs/20s1.txt
+++ b/inputs/20s1.txt
@ -0,0 +1,19 @@
+         A           
+         A           
+  #######.#########  
+  #######.........#  
+  #######.#######.#  
+  #######.#######.#  
+  #######.#######.#  
+  #####  B    ###.#  
+BC...##  C    ###.#  
+  ##.##       ###.#  
+  ##...DE  F  ###.#  
+  #####    G  ###.#  
+  #########.#####.#  
+DE..#######...###.#  
+  #.#########.###.#  
+FG..#########.....#  
+  ###########.#####  
+             Z       
+             Z       
--- a/inputs/20s2.txt
+++ b/inputs/20s2.txt
@ -0,0 +1,37 @@
+                   A               
+                   A               
+  #################.#############  
+  #.#...#...................#.#.#  
+  #.#.#.###.###.###.#########.#.#  
+  #.#.#.......#...#.....#.#.#...#  
+  #.#########.###.#####.#.#.###.#  
+  #.............#.#.....#.......#  
+  ###.###########.###.#####.#.#.#  
+  #.....#        A   C    #.#.#.#  
+  #######        S   P    #####.#  
+  #.#...#                 #......VT
+  #.#.#.#                 #.#####  
+  #...#.#               YN....#.#  
+  #.###.#                 #####.#  
+DI....#.#                 #.....#  
+  #####.#                 #.###.#  
+ZZ......#               QG....#..AS
+  ###.###                 #######  
+JO..#.#.#                 #.....#  
+  #.#.#.#                 ###.#.#  
+  #...#..DI             BU....#..LF
+  #####.#                 #.#####  
+YN......#               VT..#....QG
+  #.###.#                 #.###.#  
+  #.#...#                 #.....#  
+  ###.###    J L     J    #.#.###  
+  #.....#    O F     P    #.#...#  
+  #.###.#####.#.#####.#####.###.#  
+  #...#.#.#...#.....#.....#.#...#  
+  #.#####.###.###.#.#.#########.#  
+  #...#.#.....#...#.#.#.#.....#.#  
+  #.###.#####.###.###.#.#.#######  
+  #.#.........#...#.............#  
+  #########.###.###.#############  
+           B   J   C               
+           U   P   P               
--- a/inputs/20s3.txt
+++ b/inputs/20s3.txt
@ -0,0 +1,37 @@
+             Z L X W       C                 
+             Z P Q B       K                 
+  ###########.#.#.#.#######.###############  
+  #...#.......#.#.......#.#.......#.#.#...#  
+  ###.#.#.#.#.#.#.#.###.#.#.#######.#.#.###  
+  #.#...#.#.#...#.#.#...#...#...#.#.......#  
+  #.###.#######.###.###.#.###.###.#.#######  
+  #...#.......#.#...#...#.............#...#  
+  #.#########.#######.#.#######.#######.###  
+  #...#.#    F       R I       Z    #.#.#.#  
+  #.###.#    D       E C       H    #.#.#.#  
+  #.#...#                           #...#.#  
+  #.###.#                           #.###.#  
+  #.#....OA                       WB..#.#..ZH
+  #.###.#                           #.#.#.#  
+CJ......#                           #.....#  
+  #######                           #######  
+  #.#....CK                         #......IC
+  #.###.#                           #.###.#  
+  #.....#                           #...#.#  
+  ###.###                           #.#.#.#  
+XF....#.#                         RF..#.#.#  
+  #####.#                           #######  
+  #......CJ                       NM..#...#  
+  ###.#.#                           #.###.#  
+RE....#.#                           #......RF
+  ###.###        X   X       L      #.#.#.#  
+  #.....#        F   Q       P      #.#.#.#  
+  ###.###########.###.#######.#########.###  
+  #.....#...#.....#.......#...#.....#.#...#  
+  #####.#.###.#######.#######.###.###.#.#.#  
+  #.......#.......#.#.#.#.#...#...#...#.#.#  
+  #####.###.#####.#.#.#.#.###.###.#.###.###  
+  #.......#.....#.#...#...............#...#  
+  #############.#.#.###.###################  
+               A O F   N                     
+               A A D   M                     
--- a/main.go
+++ b/main.go
@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"runtime/pprof"
 	"strconv"
 	"strings"
 	"time"
@ -26,8 +27,10 @@ const (
 )

 var (
-	flagPart1 = flag.Bool("part1", false, "whether to run part1 or not; if no flags are present, all parts are run")
-	flagPart2 = flag.Bool("part2", false, "whether to run part2 or not; if no flags are present, all parts are run")
+	flagPart1      = flag.Bool("part1", false, "whether to run part1 or not; if no flags are present, all parts are run")
+	flagPart2      = flag.Bool("part2", false, "whether to run part2 or not; if no flags are present, all parts are run")
+	flagCpuProfile = flag.String("cpuprofile", "", "write cpu profile to file")
+	flagMemProfile = flag.String("memprofile", "", "write memory profile to file")
 )

 var dayMap = []day{
@ -47,11 +50,26 @@ var dayMap = []day{
 	&days.Day14{},
 	&days.Day15{},
 	&days.Day16{},
+	&days.Day17{},
+	&days.Day18{},
+	&days.Day19{},
+	&days.Day20{},
 }

 func main() {
 	flag.Parse()

+	if *flagCpuProfile != "" {
+		f, err := os.Create(*flagCpuProfile)
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer f.Close()
+
+		pprof.StartCPUProfile(f)
+		defer pprof.StopCPUProfile()
+	}
+
 	arg := strconv.Itoa(len(dayMap))
 	flagArgs := flag.Args()
 	if len(flagArgs) > 0 && len(flagArgs[0]) > 0 {
@ -76,7 +94,14 @@ func main() {
 		solve(dayMap[iArg-1])
 	}

-	os.Exit(0)
+	if *flagMemProfile != "" {
+		f, err := os.Create(*flagMemProfile)
+		if err != nil {
+			log.Fatal(err)
+		}
+		pprof.WriteHeapProfile(f)
+		f.Close()
+	}
 }

 func solve(d day) {
@ -96,6 +121,11 @@ func solve(d day) {
 		part1Text = d.Part1()
 	}
 	part1Time := time.Since(part1Start)
+	if runPart1 {
+		fmt.Println(part1Header)
+		fmt.Println(">", part1Text)
+		fmt.Println()
+	}

 	part2Start := time.Now()
 	var part2Text string
@ -103,17 +133,12 @@ func solve(d day) {
 		part2Text = d.Part2()
 	}
 	part2Time := time.Since(part2Start)
-
-	if runPart1 {
-		fmt.Println(part1Header)
-		fmt.Println(">", part1Text)
-		fmt.Println()
-	}
 	if runPart2 {
 		fmt.Println(part2Header)
 		fmt.Println(">", part2Text)
 		fmt.Println()
 	}
+
 	fmt.Print(utilities.ColorBrightBlack)
 	fmt.Println("Parsed in", parseTime)
 	if runPart1 {
--- a/utilities/array.go
+++ b/utilities/array.go
@ -10,3 +10,13 @@ func ArrayContains[T comparable](array []T, val T) bool {

 	return false
 }
+
+func AddToArray[V comparable, T ~[]V](arr *T, val V) bool {
+	for _, v := range *arr {
+		if v == val {
+			return false
+		}
+	}
+	*arr = append(*arr, val)
+	return true
+}
--- a/utilities/bisect.go
+++ b/utilities/bisect.go
@ -0,0 +1,26 @@
+package utilities
+
+import (
+	"math"
+)
+
+// Bisect takes a known-good low and known-bad high value as the bounds
+// to bisect, and a function to test each value for success or failure.
+// If the function succeeds, the value is adjusted toward the maximum,
+// and if the function fails, the value is adjusted toward the minimum.
+// The final value is returned when the difference between the success
+// and the failure is less than or equal to the acceptance threshold
+// (usually 1, for integers).
+func Bisect[T Number](low, high, threshold T, tryFunc func(val T) bool) T {
+	for T(math.Abs(float64(high-low))) > threshold {
+		currVal := low + ((high - low) / 2)
+		success := tryFunc(currVal)
+		if success {
+			low = currVal
+		} else {
+			high = currVal
+		}
+	}
+
+	return low
+}
--- a/utilities/intcode.go
+++ b/utilities/intcode.go
@ -128,9 +128,15 @@ func (p *IntcodeProgram) ensureMemoryCapacity(address int) {
 }

 func (p *IntcodeProgram) Reset() {
-	p.memory = nil
+	wiped := false
+	if len(p.memory) != len(p.program) {
+		wiped = true
+		p.memory = nil
+	}
 	p.init()
-	copy(p.memory, p.program)
+	if !wiped {
+		copy(p.memory, p.program)
+	}
 	p.relativeBase = 0
 }

--- a/utilities/map.go
+++ b/utilities/map.go
@ -15,3 +15,13 @@ func MapValues[T comparable, U any](m map[T]U) []U {
 	}
 	return r
 }
+
+// CopyMap returns a copy of the passed-in map. Note: currently only works if [U]
+// is not a map or slice.
+func CopyMap[T comparable, U any](m map[T]U) map[T]U {
+	r := make(map[T]U)
+	for k, v := range m {
+		r[k] = v
+	}
+	return r
+}
--- a/utilities/vector.go
+++ b/utilities/vector.go
@ -13,6 +13,8 @@ type Vec3[T Number] struct {
 	Z T
 }

+type Vec2i Vec2[int]
+
 func (v Vec2[T]) Dot(other Vec2[T]) T {
 	return (v.X * other.X) + (v.Y * other.Y)
 }
@ -42,11 +44,16 @@ func (v Vec2[T]) Equals(other Vec2[T]) bool {
 		v.Y == other.Y
 }

+func (v Vec2[T]) ManhattanDistance(other Vec2[T]) T {
+	return T(math.Abs(float64(v.X-other.X)) + math.Abs(float64(v.Y-other.Y)))
+}
+
 func VecBetween[T Number](a, b Vec2[T]) Vec2[T] {
-	return Vec2[T]{
-		X: a.X - b.X,
-		Y: a.Y - b.Y,
-	}
+	return a.To(b)
+}
+
+func ManhattanDistance[T Number](a, b Vec2[T]) T {
+	return a.ManhattanDistance(b)
 }

 func (v Vec3[T]) Dot(other Vec3[T]) T {
Author	SHA1	Message	Date
Parnic	dbc4b5cf6b	Day 20 completed The key feature for part 2 is changing up what the Dijkstra solver views as an "adjacent" node, injecting the appropriate depth as we traverse inner/outer portals. The main thing that tripped me up here from part 1 was that I needed to be carrying more data along with portals than just their locations, and I could no longer get away with storing the portals as pairs of their inner/outer locations, so a small refactor was needed. Once I made those corrections, it was mostly a matter of ironing out the "get neighbors" function to adhere to part 2's rules, which took me a lot of debugging to get just right.	2022-06-22 23:32:33 -05:00
Parnic	23a75d8f95	Day 20 part 1 This was pretty much just day 18 again, but without doors and with an input data parsing skill check. I simplified day 18 and went with a basic Dijkstra algorithm after the DFS to crawl the maze which solved this just fine. Part 2 is...ugh.	2022-06-22 16:53:03 -05:00
Parnic	c4faba7636	Day 19 solution I had some trouble with the logic of this puzzle in my head, and the visuals were too large to realistically render for me to spot-check my solution, so I kept getting part 2 wrong. I eventually realized what needed to be done to get the right answer, which was partially the realization that I needed to check +99 instead of +100, and partially that I probably didn't need to check the entire space, just the bounding points, at least for the initial filters. And then I optimized it with a bisect instead of a linear search. Always a good idea when you need to narrow a large range to a single point.	2022-06-22 16:52:32 -05:00
Parnic	982576dc68	Intcode Reset optimization Initially I noticed that I was copying twice unnecessarily (once in init() after nulling out memory, and again after returning from init()). After cleaning that up, I realized that we don't need to create a new buffer at all if the program never malloc-ed, so sometimes we can skip the re-init and we can always avoid the double-copy. I don't know if this is actually measurable anywhere, but I spot-checked some results and I still seem to be getting the same answers, so I'm gonna roll with it.	2022-06-22 16:52:32 -05:00
Parnic	19f91dbc50	Add bisect utility This is too common of an optimization to not have this readily accessible. And I kinda like how this worked out, too. Go is fun. Plus this both speeds up and "fixes" day 14's part 2 solution (it was always giving a correct answer, but mostly by chance based on how the input numbers worked out).	2022-06-22 16:52:25 -05:00
Parnic	2ef1e0656a	Day 18 solution This one was a doozy and took far more time than I'd like to admit. I hope it's the hardest problem of the year. My original solution gave correct answers, but took on the order of 3+ minutes to run, even with memoization (it wasn't finishing any time soon without it). I then tried dropping in some A* and Dijkstra libraries, but wasn't really happy with how things were progressing with them. Some research pointed me toward double-ended queues and priority queues as better solutions, which I should have come up with my own since they've been used along with memoization in other AoC's, and dropping those in took the runtimes down to 4-15 seconds on my m1 macbook air. Once I swapped out the memoized data structures from arrays to maps, the runtime finally dropped to a much more palatable 50-180 millisecond range. I'm always suspicious when my solution is hundreds of lines of code, though, since you tend to see much more terse solutions from others in the AoC subreddit, but I attribute at least some of the bloat to "Go things" like how maps and arrays usually need to be "make"d first, how there's no easy "list comprehension" or "linq" style data structure queries, etc. Finally: note that I've seen _dramatically_ different runtimes based on the input. One set of input I checked against ran in 30ms/10ms while another ran in 180ms/54ms. I guess it's never been promised that all inputs are created equally...	2022-06-22 16:52:18 -05:00
Parnic	a0867490c9	Add utility for array AddUnique	2022-06-18 23:07:38 -05:00
Parnic	3d3ea6e266	Add support for cpu and memory profiling My day 18 was slow and I wasn't completely certain where it was all coming from, so I dove into Go's profiling stuff. It was super helpful in identifying the problem and giving me easy wins that took runtime from 4.6s/14.4s (part 1/part 2) to 180ms/50ms just from swapping some arrays for maps, which the profile pointed out very clearly.	2022-06-18 23:07:38 -05:00
Parnic	4b5bd0d4e0	Display part1 output as soon as it's ready When we start having problems that take a while to run, it sucks to have to wait for everything to finish before we see any output.	2022-06-18 22:49:28 -05:00
Parnic	5bc089c83d	Day 17 solution My initial idea for a solution ended up working out great, but I had a hard time getting it all down on "paper," so to speak, so this is probably 200 lines of code too many, but it definitely does exactly what I envisioned (and quickly) even if it's not the most succinct.	2022-06-14 14:37:06 -05:00
				`@ -0,0 +1 @@`
				1,330,331,332,109,2734,1102,1182,1,15,1102,1,1429,24,1002,0,1,570,1006,570,36,1001,571,0,0,1001,570,-1,570,1001,24,1,24,1106,0,18,1008,571,0,571,1001,15,1,15,1008,15,1429,570,1006,570,14,21102,58,1,0,1105,1,786,1006,332,62,99,21101,0,333,1,21102,73,1,0,1105,1,579,1101,0,0,572,1101,0,0,573,3,574,101,1,573,573,1007,574,65,570,1005,570,151,107,67,574,570,1005,570,151,1001,574,-64,574,1002,574,-1,574,1001,572,1,572,1007,572,11,570,1006,570,165,101,1182,572,127,1001,574,0,0,3,574,101,1,573,573,1008,574,10,570,1005,570,189,1008,574,44,570,1006,570,158,1105,1,81,21102,1,340,1,1105,1,177,21101,0,477,1,1106,0,177,21101,0,514,1,21101,0,176,0,1106,0,579,99,21102,1,184,0,1106,0,579,4,574,104,10,99,1007,573,22,570,1006,570,165,1001,572,0,1182,21102,1,375,1,21101,211,0,0,1106,0,579,21101,1182,11,1,21102,1,222,0,1105,1,979,21102,1,388,1,21102,233,1,0,1105,1,579,21101,1182,22,1,21101,0,244,0,1106,0,979,21101,401,0,1,21101,0,255,0,1105,1,579,21101,1182,33,1,21102,266,1,0,1106,0,979,21102,1,414,1,21102,1,277,0,1106,0,579,3,575,1008,575,89,570,1008,575,121,575,1,575,570,575,3,574,1008,574,10,570,1006,570,291,104,10,21102,1182,1,1,21101,313,0,0,1106,0,622,1005,575,327,1102,1,1,575,21102,327,1,0,1105,1,786,4,438,99,0,1,1,6,77,97,105,110,58,10,33,10,69,120,112,101,99,116,101,100,32,102,117,110,99,116,105,111,110,32,110,97,109,101,32,98,117,116,32,103,111,116,58,32,0,12,70,117,110,99,116,105,111,110,32,65,58,10,12,70,117,110,99,116,105,111,110,32,66,58,10,12,70,117,110,99,116,105,111,110,32,67,58,10,23,67,111,110,116,105,110,117,111,117,115,32,118,105,100,101,111,32,102,101,101,100,63,10,0,37,10,69,120,112,101,99,116,101,100,32,82,44,32,76,44,32,111,114,32,100,105,115,116,97,110,99,101,32,98,117,116,32,103,111,116,58,32,36,10,69,120,112,101,99,116,101,100,32,99,111,109,109,97,32,111,114,32,110,101,119,108,105,110,101,32,98,117,116,32,103,111,116,58,32,43,10,68,101,102,105,110,105,116,105,111,110,115,32,109,97,121,32,98,101,32,97,116,32,109,111,115,116,32,50,48,32,99,104,97,114,97,99,116,101,114,115,33,10,94,62,118,60,0,1,0,-1,-1,0,1,0,0,0,0,0,0,1,6,0,0,109,4,1202,-3,1,587,20101,0,0,-1,22101,1,-3,-3,21101,0,0,-2,2208,-2,-1,570,1005,570,617,2201,-3,-2,609,4,0,21201,-2,1,-2,1105,1,597,109,-4,2106,0,0,109,5,2102,1,-4,630,20102,1,0,-2,22101,1,-4,-4,21102,0,1,-3,2208,-3,-2,570,1005,570,781,2201,-4,-3,652,21002,0,1,-1,1208,-1,-4,570,1005,570,709,1208,-1,-5,570,1005,570,734,1207,-1,0,570,1005,570,759,1206,-1,774,1001,578,562,684,1,0,576,576,1001,578,566,692,1,0,577,577,21101,0,702,0,1105,1,786,21201,-1,-1,-1,1106,0,676,1001,578,1,578,1008,578,4,570,1006,570,724,1001,578,-4,578,21101,0,731,0,1106,0,786,1105,1,774,1001,578,-1,578,1008,578,-1,570,1006,570,749,1001,578,4,578,21101,0,756,0,1106,0,786,1106,0,774,21202,-1,-11,1,22101,1182,1,1,21102,774,1,0,1105,1,622,21201,-3,1,-3,1105,1,640,109,-5,2106,0,0,109,7,1005,575,802,21002,576,1,-6,20101,0,577,-5,1105,1,814,21102,1,0,-1,21102,1,0,-5,21102,0,1,-6,20208,-6,576,-2,208,-5,577,570,22002,570,-2,-2,21202,-5,29,-3,22201,-6,-3,-3,22101,1429,-3,-3,1202,-3,1,843,1005,0,863,21202,-2,42,-4,22101,46,-4,-4,1206,-2,924,21102,1,1,-1,1105,1,924,1205,-2,873,21102,1,35,-4,1105,1,924,1202,-3,1,878,1008,0,1,570,1006,570,916,1001,374,1,374,2101,0,-3,895,1101,2,0,0,2102,1,-3,902,1001,438,0,438,2202,-6,-5,570,1,570,374,570,1,570,438,438,1001,578,558,922,20101,0,0,-4,1006,575,959,204,-4,22101,1,-6,-6,1208,-6,29,570,1006,570,814,104,10,22101,1,-5,-5,1208,-5,45,570,1006,570,810,104,10,1206,-1,974,99,1206,-1,974,1101,1,0,575,21101,973,0,0,1105,1,786,99,109,-7,2105,1,0,109,6,21101,0,0,-4,21102,1,0,-3,203,-2,22101,1,-3,-3,21208,-2,82,-1,1205,-1,1030,21208,-2,76,-1,1205,-1,1037,21207,-2,48,-1,1205,-1,1124,22107,57,-2,-1,1205,-1,1124,21201,-2,-48,-2,1105,1,1041,21102,-4,1,-2,1106,0,1041,21101,-5,0,-2,21201,-4,1,-4,21207,-4,11,-1,1206,-1,1138,2201,-5,-4,1059,1201,-2,0,0,203,-2,22101,1,-3,-3,21207,-2,48,-1,1205,-1,1107,22107,57,-2,-1,1205,-1,1107,21201,-2,-48,-2,2201,-5,-4,1090,20102,10,0,-1,22201,-2,-1,-2,2201,-5,-4,1103,2101,0,-2,0,1106,0,1060,21208,-2,10,-1,1205,-1,1162,21208,-2,44,-1,1206,-1,1131,1105,1,989,21101,439,0,1,1105,1,1150,21102,1,477,1,1105,1,1150,21102,1,514,1,21102,1,1149,0,1105,1,579,99,21101,1157,0,0,1106,0,579,204,-2,104,10,99,21207,-3,22,-1,1206,-1,1138,2101,0,-5,1176,1202,-4,1,0,109,-6,2105,1,0,6,5,28,1,28,1,28,1,28,1,28,1,20,11,1,7,10,1,7,1,1,1,1,1,5,1,10,1,5,11,1,1,10,1,5,1,1,1,1,1,1,1,3,1,1,1,10,9,1,1,1,1,1,5,16,1,3,1,1,1,1,1,1,1,18,5,1,1,1,1,1,1,24,1,1,1,1,1,24,1,1,1,1,1,24,1,1,1,1,1,24,5,7,1,18,1,9,1,18,1,9,1,18,1,9,1,18,1,9,1,18,1,9,1,12,7,9,1,12,1,15,1,12,1,15,1,12,1,15,1,12,1,15,1,12,1,15,1,2,5,5,1,9,7,2,1,3,1,5,1,9,1,8,1,3,1,5,1,9,1,8,1,3,1,5,1,9,1,8,1,3,13,3,1,8,1,9,1,5,1,3,1,8,11,5,1,1,5,22,1,1,1,1,1,1,1,22,1,1,1,1,1,1,1,22,1,1,1,1,1,1,1,22,13,18,1,1,1,1,1,5,1,16,5,1,1,5,1,16,1,1,1,3,1,5,1,16,1,1,11,16,1,5,1,22,7,6
				`@ -0,0 +1 @@`
				109,424,203,1,21102,11,1,0,1105,1,282,21101,0,18,0,1105,1,259,2101,0,1,221,203,1,21102,1,31,0,1105,1,282,21102,1,38,0,1105,1,259,20102,1,23,2,21201,1,0,3,21102,1,1,1,21102,57,1,0,1106,0,303,2102,1,1,222,21002,221,1,3,20101,0,221,2,21101,0,259,1,21101,0,80,0,1105,1,225,21101,44,0,2,21102,91,1,0,1105,1,303,1202,1,1,223,21002,222,1,4,21102,259,1,3,21102,1,225,2,21102,225,1,1,21101,118,0,0,1106,0,225,21002,222,1,3,21101,163,0,2,21101,0,133,0,1106,0,303,21202,1,-1,1,22001,223,1,1,21102,148,1,0,1106,0,259,1202,1,1,223,20101,0,221,4,21001,222,0,3,21102,1,24,2,1001,132,-2,224,1002,224,2,224,1001,224,3,224,1002,132,-1,132,1,224,132,224,21001,224,1,1,21101,195,0,0,105,1,108,20207,1,223,2,21002,23,1,1,21102,-1,1,3,21102,1,214,0,1106,0,303,22101,1,1,1,204,1,99,0,0,0,0,109,5,2101,0,-4,249,22102,1,-3,1,22101,0,-2,2,22101,0,-1,3,21102,250,1,0,1106,0,225,21202,1,1,-4,109,-5,2105,1,0,109,3,22107,0,-2,-1,21202,-1,2,-1,21201,-1,-1,-1,22202,-1,-2,-2,109,-3,2106,0,0,109,3,21207,-2,0,-1,1206,-1,294,104,0,99,22102,1,-2,-2,109,-3,2105,1,0,109,5,22207,-3,-4,-1,1206,-1,346,22201,-4,-3,-4,21202,-3,-1,-1,22201,-4,-1,2,21202,2,-1,-1,22201,-4,-1,1,21202,-2,1,3,21101,0,343,0,1106,0,303,1106,0,415,22207,-2,-3,-1,1206,-1,387,22201,-3,-2,-3,21202,-2,-1,-1,22201,-3,-1,3,21202,3,-1,-1,22201,-3,-1,2,21201,-4,0,1,21101,384,0,0,1105,1,303,1105,1,415,21202,-4,-1,-4,22201,-4,-3,-4,22202,-3,-2,-2,22202,-2,-4,-4,22202,-3,-2,-3,21202,-4,-1,-2,22201,-3,-2,1,21202,1,1,-4,109,-5,2105,1,0