advent-of-code/2020
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

2-3x perf improvement for fun

Browse Source 
The adjacent checking functions are still embarrassing, though...
This commit is contained in:
Chris Pickett
2020-12-11 09:34:46 -06:00
parent ac23dd44bf
commit aa8d9b5fdb
1 changed files with 28 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files

52
Q11.cs
View File

@ -1,6 +1,8 @@
using System; using System;
using System.Diagnostics; using System.Diagnostics;
using System.IO; using System.IO;
using System.Threading;
using System.Threading.Tasks;
namespace _2020 namespace _2020
{ {
@ -189,6 +191,22 @@ namespace _2020
return numOccupied; return numOccupied;
} }
static int GetNumOccupied(SeatState[,] currState)
{
int totalNumOccupied = 0;
for (int i = 0; i < numRows; i++)
{
for (int j = 0; j < numCols; j++)
{
if (currState[i, j] == SeatState.Occupied)
{
totalNumOccupied++;
}
}
}
return totalNumOccupied;
}
static void Part1() static void Part1()
{ {
SeatState[,] currState = new SeatState[numRows, numCols]; SeatState[,] currState = new SeatState[numRows, numCols];
@ -196,15 +214,13 @@ namespace _2020
Array.Copy(list, currState, numRows * numCols); Array.Copy(list, currState, numRows * numCols);
int rounds = 0; int rounds = 0;
int totalNumOccupied = 0;
for (int numChanges = 0; rounds == 0 || numChanges != 0; rounds++) for (int numChanges = 0; rounds == 0 || numChanges != 0; rounds++)
{ {
Array.Copy(currState, nextState, numRows * numCols); Array.Copy(currState, nextState, numRows * numCols);
totalNumOccupied = 0;
numChanges = 0; numChanges = 0;
for (int i = 0; i < numRows; i++) Parallel.For(0, numRows, (i) =>
{ {
for (int j = 0; j < numCols; j++) for (int j = 0; j < numCols; j++)
{ {
@ -212,25 +228,20 @@ namespace _2020
if (currState[i, j] == SeatState.Empty && numOccupied == 0) if (currState[i, j] == SeatState.Empty && numOccupied == 0)
{ {
nextState[i, j] = SeatState.Occupied; nextState[i, j] = SeatState.Occupied;
numChanges++; Interlocked.Increment(ref numChanges);
} }
else if (currState[i, j] == SeatState.Occupied && numOccupied >= 4) else if (currState[i, j] == SeatState.Occupied && numOccupied >= 4)
{ {
nextState[i, j] = SeatState.Empty; nextState[i, j] = SeatState.Empty;
numChanges++; Interlocked.Increment(ref numChanges);
}
if (nextState[i, j] == SeatState.Occupied)
{
totalNumOccupied++;
}
} }
} }
});
Array.Copy(nextState, currState, numRows * numCols); Array.Copy(nextState, currState, numRows * numCols);
} }
Debug.WriteLine($"Q11Part1: stabilized after {rounds - 1} rounds, total occupied={totalNumOccupied}"); Debug.WriteLine($"Q11Part1: stabilized after {rounds - 1} rounds, total occupied={GetNumOccupied(currState)}");
} }
static void Part2() static void Part2()
@ -240,15 +251,13 @@ namespace _2020
Array.Copy(list, currState, numRows * numCols); Array.Copy(list, currState, numRows * numCols);
int rounds = 0; int rounds = 0;
int totalNumOccupied = 0;
for (int numChanges = 0; rounds == 0 || numChanges != 0; rounds++) for (int numChanges = 0; rounds == 0 || numChanges != 0; rounds++)
{ {
Array.Copy(currState, nextState, numRows * numCols); Array.Copy(currState, nextState, numRows * numCols);
totalNumOccupied = 0;
numChanges = 0; numChanges = 0;
for (int i = 0; i < numRows; i++) Parallel.For(0, numRows, (i) =>
{ {
for (int j = 0; j < numCols; j++) for (int j = 0; j < numCols; j++)
{ {
@ -256,25 +265,20 @@ namespace _2020
if (currState[i, j] == SeatState.Empty && numOccupied == 0) if (currState[i, j] == SeatState.Empty && numOccupied == 0)
{ {
nextState[i, j] = SeatState.Occupied; nextState[i, j] = SeatState.Occupied;
numChanges++; Interlocked.Increment(ref numChanges);
} }
else if (currState[i, j] == SeatState.Occupied && numOccupied >= 5) else if (currState[i, j] == SeatState.Occupied && numOccupied >= 5)
{ {
nextState[i, j] = SeatState.Empty; nextState[i, j] = SeatState.Empty;
numChanges++; Interlocked.Increment(ref numChanges);
}
if (nextState[i, j] == SeatState.Occupied)
{
totalNumOccupied++;
}
} }
} }
});
Array.Copy(nextState, currState, numRows * numCols); Array.Copy(nextState, currState, numRows * numCols);
} }
Debug.WriteLine($"Q11Part2: stabilized after {rounds - 1} rounds, total occupied={totalNumOccupied}"); Debug.WriteLine($"Q11Part2: stabilized after {rounds - 1} rounds, total occupied={GetNumOccupied(currState)}");
} }
} }
} }