diff --git a/advent-of-code-2023.csproj b/advent-of-code-2023.csproj
index c50afe0..6ad3f80 100644
--- a/advent-of-code-2023.csproj
+++ b/advent-of-code-2023.csproj
@@ -75,6 +75,8 @@
+
+
@@ -89,4 +91,8 @@
+
+
+
+
diff --git a/inputs/24.txt b/inputs/24.txt
new file mode 100644
index 0000000..f9e9e05
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+278452443212631, 269128033327091, 368778544617365 @ -23, 39, -130
+116850894919422, 230400566950229, 165050987749346 @ 302, 135, 207
+260697705868248, 331507689359744, 230934509869239 @ 58, -46, 62
+345883734794082, 404319736386014, 165508639034243 @ -96, -266, 188
+338518007127116, 197895428534989, 333026065429020 @ -82, 441, -363
+501219359367120, 412285025575991, 553543190879582 @ -374, -193, -381
+315802188788550, 335952206092989, 221378550288190 @ 46, 19, -64
+318355888692006, 379462736241893, 346108974688070 @ -62, -151, -208
+258432198353802, 116363585901746, 279158788196090 @ 48, 384, -25
+331495566132405, 329696949720270, 262637093449293 @ -71, -12, -88
+225128317377718, 98339882122589, 405612346982306 @ 9, 212, -89
+339590953497350, 387529697719375, 418409016132703 @ -60, -209, -930
+188156378042670, 144991106399203, 54479747459418 @ 76, 180, 363
+189508861409856, 220025770701113, 300342334256882 @ 39, 47, 55
+355470936519087, 377588730568583, 186025958729126 @ -123, -173, 67
+357617990656670, 278931805125261, 301898192453698 @ -154, 34, -37
+213886629816471, 247221744883994, 187412927602760 @ 117, 102, 165
+296374173800760, 169384218125771, 83441210687864 @ 111, 694, 524
+236639955898698, 151938093144053, 194945971221898 @ 67, 269, 153
+288917518632726, 492724869524685, 228500513113072 @ -8, -387, 72
+295727746197582, 360474744238229, 503124831753782 @ -68, -115, -270
+282189594610170, 282491392005509, 436551439705984 @ -74, -31, -88
+314954230601466, 420548190234857, 214580005953260 @ 64, -371, -51
+357847064816890, 337336638576149, 184267494146994 @ -109, 197, -61
+348706752056672, 275377145397879, 169020924918062 @ -73, 460, 145
+214663556424384, 302115053921987, 548387355035240 @ -15, -60, -170
+137816123354705, 68881532714919, 90822718496989 @ 141, 279, 312
+248891797596266, 313785440491389, 60802879347282 @ 89, -5, 435
+469165669056299, 304541996543790, 499226179275000 @ -271, -62, -123
+265821000515835, 161895492455969, 181634450597243 @ 11, 245, 178
+356285242983476, 347728362889153, 158843970135404 @ -81, 127, 196
+324775129764550, 347016718050565, 202162951243018 @ 159, 57, -160
+235138827258360, 84780944337545, 375637426198508 @ 19, 279, -90
+207155653686690, 268708428643649, 269113419224924 @ 216, 117, -51
+328903202326354, 314642642432431, 231385235953726 @ -42, 66, -43
+351348584362654, 328210234088285, 183423860793722 @ -46, 278, -44
+133923271127655, 15946363179440, 218432342211833 @ 77, 244, 158
+261067422616210, 294587005892105, 54887803745498 @ 71, 44, 457
+331821353676594, 422141575447479, 299518708308799 @ 40, -473, -706
+369931379292600, 277109566356635, 291555687461348 @ -207, 460, -640
+271201570580361, 319931769006502, 233949945157639 @ 37, -20, 54
+219929906219867, 351074327917355, 267765680025459 @ 77, -97, 36
+292339075455432, 199741793871233, 285373325473232 @ -71, 95, 54
+346900087043760, 288681201410123, 253127416209530 @ -114, 119, -73
+347544901928734, 345957012938925, 155174759798780 @ 68, 213, 244
+241918384900110, 396704843204545, 178323238720558 @ 76, -182, 180
+305784694247844, 291026924781121, 547325893026114 @ -77, -9, -369
\ No newline at end of file
diff --git a/inputs/24a.txt b/inputs/24a.txt
new file mode 100644
index 0000000..cbe1492
--- /dev/null
+++ b/inputs/24a.txt
@@ -0,0 +1,5 @@
+19, 13, 30 @ -2, 1, -2
+18, 19, 22 @ -1, -1, -2
+20, 25, 34 @ -2, -2, -4
+12, 31, 28 @ -1, -2, -1
+20, 19, 15 @ 1, -5, -3
\ No newline at end of file
diff --git a/src/24.cs b/src/24.cs
new file mode 100644
index 0000000..2b9db3e
--- /dev/null
+++ b/src/24.cs
@@ -0,0 +1,132 @@
+using System.Numerics;
+using aoc2023.Util;
+using Microsoft.Z3;
+
+namespace aoc2023;
+
+internal class Day24 : Day
+{
+ class path
+ {
+ public readonly ivec3 startPos;
+ public readonly ivec3 velocity;
+
+ public readonly BigInteger a;
+ public readonly BigInteger b;
+ public readonly BigInteger c;
+
+ public path(ivec3 p, ivec3 v)
+ {
+ startPos = p;
+ velocity = v;
+
+ a = velocity.y;
+ b = -velocity.x;
+ c = velocity.y * startPos.x - velocity.x * startPos.y;
+ }
+
+ public override string ToString() => $"{startPos} @ {velocity}";
+ }
+
+ private readonly List hailstones = [];
+ internal override void Parse()
+ {
+ var lines = Parsing.ReadAllLines($"{GetDay()}");
+ foreach (var line in lines)
+ {
+ var split = line.Split(" @ ").Select(x => x.Replace(" ", "")).ToList();
+ path p = new(ivec3.Parse(split[0]), ivec3.Parse(split[1]));
+ hailstones.Add(p);
+ }
+ }
+
+ internal override string Part1()
+ {
+ BigInteger lowerBound = 200000000000000;
+ BigInteger upperBound = 400000000000000;
+ long total = 0;
+ for (int i = 0; i < hailstones.Count; i++)
+ {
+ for (int j = 0; j < i; j++)
+ {
+ var (a1, b1, c1) = (hailstones[i].a, hailstones[i].b, hailstones[i].c);
+ var (a2, b2, c2) = (hailstones[j].a, hailstones[j].b, hailstones[j].c);
+ if (a1 * b2 == b1 * a2)
+ {
+ continue;
+ }
+
+ var x = (c1 * b2 - c2 * b1) / (a1 * b2 - a2 * b1);
+ var y = (c2 * a1 - c1 * a2) / (a1 * b2 - a2 * b1);
+ if (x < lowerBound || x > upperBound || y < lowerBound || y > upperBound)
+ {
+ continue;
+ }
+
+ if ((x - hailstones[i].startPos.x) * hailstones[i].velocity.x >= 0 && (y - hailstones[i].startPos.y) * hailstones[i].velocity.y >= 0 &&
+ (x - hailstones[j].startPos.x) * hailstones[j].velocity.x >= 0 && (y - hailstones[j].startPos.y) * hailstones[j].velocity.y >= 0)
+ {
+ total++;
+ }
+ }
+ }
+
+ return $"Intersections: <+white>{total}";
+ }
+
+ internal override string Part2()
+ {
+ var ctx = new Context();
+ var solver = ctx.MkSolver();
+
+ // Coordinates of the stone
+ var x = ctx.MkIntConst("x");
+ var y = ctx.MkIntConst("y");
+ var z = ctx.MkIntConst("z");
+
+ // Velocity of the stone
+ var vx = ctx.MkIntConst("vx");
+ var vy = ctx.MkIntConst("vy");
+ var vz = ctx.MkIntConst("vz");
+
+ // For each iteration, we will add 3 new equations and one new condition to the solver.
+ // We want to find 9 variables (x, y, z, vx, vy, vz, t0, t1, t2) that satisfy all the equations, so a system of 9 equations is enough.
+ for (var i = 0; i < 3; i++)
+ {
+ var t = ctx.MkIntConst($"t{i}"); // time for the stone to reach the hail
+ var hail = hailstones[i];
+
+ var px = ctx.MkInt(hail.startPos.x);
+ var py = ctx.MkInt(hail.startPos.y);
+ var pz = ctx.MkInt(hail.startPos.z);
+
+ var pvx = ctx.MkInt(hail.velocity.x);
+ var pvy = ctx.MkInt(hail.velocity.y);
+ var pvz = ctx.MkInt(hail.velocity.z);
+
+ var xLeft = ctx.MkAdd(x, ctx.MkMul(t, vx)); // x + t * vx
+ var yLeft = ctx.MkAdd(y, ctx.MkMul(t, vy)); // y + t * vy
+ var zLeft = ctx.MkAdd(z, ctx.MkMul(t, vz)); // z + t * vz
+
+ var xRight = ctx.MkAdd(px, ctx.MkMul(t, pvx)); // px + t * pvx
+ var yRight = ctx.MkAdd(py, ctx.MkMul(t, pvy)); // py + t * pvy
+ var zRight = ctx.MkAdd(pz, ctx.MkMul(t, pvz)); // pz + t * pvz
+
+ solver.Add(t >= 0); // time should always be positive - we don't want solutions for negative time
+ solver.Add(ctx.MkEq(xLeft, xRight)); // x + t * vx = px + t * pvx
+ solver.Add(ctx.MkEq(yLeft, yRight)); // y + t * vy = py + t * pvy
+ solver.Add(ctx.MkEq(zLeft, zRight)); // z + t * vz = pz + t * pvz
+ }
+
+ solver.Check();
+ var model = solver.Model;
+
+ var rx = model.Eval(x);
+ var ry = model.Eval(y);
+ var rz = model.Eval(z);
+
+ long result = long.Parse(rx.ToString()) + long.Parse(ry.ToString()) + long.Parse(rz.ToString());
+
+ return $"Added coordinates of rock-throwing position: <+white>{result}";
+ }
+}