diff --git a/solvers/UNeverTellMeTheOdds.pas b/solvers/UNeverTellMeTheOdds.pas
index 6f5c98d..b4b2e82 100644
--- a/solvers/UNeverTellMeTheOdds.pas
+++ b/solvers/UNeverTellMeTheOdds.pas
@@ -1,6 +1,6 @@
 {
   Solutions to the Advent Of Code.
-  Copyright (C) 2023  Stefan Müller
+  Copyright (C) 2023-2024  Stefan Müller
 
   This program is free software: you can redistribute it and/or modify it under
   the terms of the GNU General Public License as published by the Free Software
@@ -22,26 +22,45 @@ unit UNeverTellMeTheOdds;
 interface
 
 uses
-  Classes, SysUtils, Generics.Collections, Math, USolver;
+  Classes, SysUtils, Generics.Collections, Math, matrix, USolver, UNumberTheory, UBigInt;
 
 type
 
   { THailstone }
 
-  THailstone = record
-    X, Y, Z: Int64;
-    VX, VY, VZ: Integer;
+  THailstone = class
+  public
+    Position, Velocity: Tvector3_extended;
+    constructor Create(const ALine: string);
+    constructor Create(const APosition, AVelocity: Tvector3_extended);
   end;
 
-  THailstones = specialize TList<THailstone>;
+  THailstones = specialize TObjectList<THailstone>;
+
+  { TFirstCollisionPolynomial }
+
+  TFirstCollisionPolynomial = class
+  private
+    FA: array[0..10] of TBigInt;
+    FH: array[0..6] of TBigInt;
+    procedure NormalizeCoefficients;
+  public
+    procedure Init(constref AHailstone1, AHailstone2, AHailstone3: THailstone; const t_0, t_1, t_2: Int64);
+    function EvaluateAt(const AT0: Int64): TBigInt;
+    function CalcPositiveIntegerRoot: Int64;
+    function CalcT1(const AT0: Int64): Int64;
+  end;
 
   { TNeverTellMeTheOdds }
 
   TNeverTellMeTheOdds = class(TSolver)
   private
     FMin, FMax: Int64;
-    FHailStones: THailstones;
+    FHailstones: THailstones;
+    FA: array[0..10] of Int64;
+    FH: array[0..6] of Int64;
     function AreIntersecting(constref AHailstone1, AHailstone2: THailstone): Boolean;
+    procedure FindRockThrow(const AIndex1, AIndex2, AIndex3: Integer);
   public
     constructor Create(const AMin: Int64 = 200000000000000; const AMax: Int64 = 400000000000000);
     destructor Destroy; override;
@@ -51,8 +70,452 @@ type
     function GetPuzzleName: string; override;
   end;
 
+const
+  CIterationThreshold = 0.00001;
+  CEpsilon = 0.0000000001;
+
 implementation
 
+{ THailstone }
+
+constructor THailstone.Create(const ALine: string);
+var
+  split: TStringArray;
+begin
+  split := ALine.Split([',', '@']);
+  Position.init(
+    StrToFloat(Trim(split[0])),
+    StrToFloat(Trim(split[1])),
+    StrToFloat(Trim(split[2])));
+  Velocity.init(
+    StrToFloat(Trim(split[3])),
+    StrToFloat(Trim(split[4])),
+    StrToFloat(Trim(split[5])));
+end;
+
+constructor THailstone.Create(const APosition, AVelocity: Tvector3_extended);
+begin
+  Position := APosition;
+  Velocity := AVelocity;
+end;
+
+{ TFirstCollisionPolynomial }
+
+procedure TFirstCollisionPolynomial.NormalizeCoefficients;
+var
+  shift: Integer;
+  i: Low(FA)..High(FA);
+  //gcd: TBigInt;
+begin
+  // Eliminates zero constant term.
+  shift := 0;
+  while (shift <= High(FA)) and (FA[shift] = 0) do
+    Inc(shift);
+
+  if shift <= High(FA) then
+  begin
+    if shift > 0 then
+    begin
+      for i := Low(FA) to High(FA) - shift do
+        FA[i] := FA[i + shift];
+      for i := High(FA) - shift + 1 to High(FA) do
+        FA[i] := 0;
+    end;
+
+    //// Finds GCD of all coefficients.
+    //gcd := FA[Low(FA)];
+    //for i := Low(FA) + 1 to High(FA) do
+    //  if FA[i] <> 0 then
+    //    gcd := TNumberTheory.GreatestCommonDivisor(gcd, FA[i]);
+    //WriteLn('GCD: ', gcd);
+    //
+    //for i := Low(FA) to High(FA) do
+    //  FA[i] := FA[i] div gcd;
+  end;
+
+  //WriteLn('(', FA[10], ') * x^10 + (', FA[9], ') * x^9 + (', FA[8], ') * x^8 + (', FA[7], ') * x^7 + (',
+  //  FA[6], ') * x^6 + (', FA[5], ') * x^5 + (', FA[4], ') * x^4 + (', FA[3], ') * x^3 + (', FA[2], ') * x^2 + (',
+  //  FA[1], ') * x + (', FA[0], ')');
+end;
+
+procedure TFirstCollisionPolynomial.Init(constref AHailstone1, AHailstone2, AHailstone3: THailstone; const t_0, t_1,
+  t_2: Int64);
+var
+  P_00, P_01, P_02, P_10, P_11, P_12, P_20, P_21, P_22,
+  V_00, V_01, V_02, V_10, V_11, V_12, V_20, V_21, V_22: Int64;
+  k: array[0..139] of TBigInt;
+  // For debug calculations
+  act, a_1, a_2, b_0, b_1, c_0, c_1, d_0, d_1, e_0, e_1, f_0, f_1, f_2: Int64;
+begin
+  // Solving this non-linear equation system, with velocities V_i and start positions P_i:
+  //   V_0 * t_0 + P_0 = V_x * t_0 + P_x
+  //   V_1 * t_1 + P_1 = V_x * t_1 + P_x
+  //   V_2 * t_2 + P_2 = V_x * t_2 + P_x
+  // Which gives:
+  //   P_x = (V_0 - V_x) * t_0 + P_0
+  //   V_x = (V_0 * t_0 - V_1 * t_1 + P_0 - P_1) / (t_0 - t_1)
+  // And with vertex components:
+  //   1: 0 = (t_1 - t_0) * (V_00 * t_0 - V_20 * t_2 + P_00 - P_20) - (t_2 - t_0) * (V_00 * t_0 - V_10 * t_1 + P_00 - P_10)
+  //   2: t_1 = (((V_01 - V_21) * t_2 + P_11 - P_21) * t_0 + (P_01 - P_11) * t_2)
+  //            / ((V_01 - V_11) * t_0 + (V_11 - V_21) * t_2 + P_01 - P_21)
+  //   3: t_2 = (((V_02 - V_12) * t_1 + P_22 - P_12) * t_0 + (P_02 - P_22) * t_1)
+  //            / ((V_02 - V_22) * t_0 + (V_22 - V_12) * t_1 + P_02 - P_12)
+  //   for t_0, t_1, t_2 not pairwise equal.
+  // With some substitutions depending only on t_0 this gives
+  //   1: 0 = (t_1 - t_0) * (f_2 - V_20 * t_2) - (t_2 - t_0) * (f_1 - V_10 * t_1)
+  //   2: t_1 = (b_0 + b_1 * t_2) / (c_0 + c_1 * t_2)
+  //   3: t_2 = (d_0 + d_1 * t_1) / (e_0 + e_1 * t_1)
+  // And 3 in 2 gives:
+  //   4: g_2 * t_1^2 - g_1 * t_1 - g_0 = 0
+  // Then, with 4 and 3 in 1 and lengthy calculations with many substitutions (see constants k below, now independent of
+  // t_0), the following polynomial can be constructed, with t_0 being a positive integer root of this polynomial.
+  //   y = a_10 * x^10 + a_9 * x^9 + ... + a_0
+
+  P_00 := Round(AHailstone1.Position.data[0]);
+  P_01 := Round(AHailstone1.Position.data[1]);
+  P_02 := Round(AHailstone1.Position.data[2]);
+  P_10 := Round(AHailstone2.Position.data[0]);
+  P_11 := Round(AHailstone2.Position.data[1]);
+  P_12 := Round(AHailstone2.Position.data[2]);
+  P_20 := Round(AHailstone3.Position.data[0]);
+  P_21 := Round(AHailstone3.Position.data[1]);
+  P_22 := Round(AHailstone3.Position.data[2]);
+  V_00 := Round(AHailstone1.Velocity.data[0]);
+  V_01 := Round(AHailstone1.Velocity.data[1]);
+  V_02 := Round(AHailstone1.Velocity.data[2]);
+  V_10 := Round(AHailstone2.Velocity.data[0]);
+  V_11 := Round(AHailstone2.Velocity.data[1]);
+  V_12 := Round(AHailstone2.Velocity.data[2]);
+  V_20 := Round(AHailstone3.Velocity.data[0]);
+  V_21 := Round(AHailstone3.Velocity.data[1]);
+  V_22 := Round(AHailstone3.Velocity.data[2]);
+
+  k[0] := P_00 - P_20;
+  k[1] := P_00 - P_10;
+  k[2] := P_11 - P_21;
+  k[3] := P_01 - P_11;
+  k[4] := P_01 - P_21;
+  k[5] := P_22 - P_12;
+  k[6] := P_02 - P_22;
+  k[7] := P_02 - P_12;
+  k[8] := V_11 - V_21;
+  k[9] := V_22 - V_12;
+  k[10] := V_01 - V_21;
+  k[11] := V_01 - V_11;
+  k[12] := V_02 - V_12;
+  k[13] := V_02 - V_22;
+
+  FH[0] := k[11] * k[9] + k[8] * k[12];
+  FH[1] := k[4] * k[9] + k[8] * k[6];
+  FH[2] := k[11] * k[13] - k[10] * k[12];
+  FH[3] := k[11] * k[7] + k[4] * k[13] + k[8] * k[5] - k[2] * k[9] - k[10] * k[6] - k[3] * k[12];
+  FH[4] := k[4] * k[7] - k[3] * k[6];
+  FH[5] := k[10] * k[5] + k[2] * k[13];
+  FH[6] := k[3] * k[5] + k[2] * k[7];
+
+  k[14] := V_00 * k[9] - V_20 * k[12];
+  k[15] := k[0] * k[9] - V_20 * k[6];
+  k[16] := V_00 * k[13];
+  k[17] := V_00 * k[7] + k[0] * k[13] - V_20 * k[5];
+  k[18] := k[0] * k[7];
+  k[19] := k[5] - k[7];
+  k[20] := 2 * FH[2] * FH[3];
+  k[21] := FH[3] * FH[3];
+  k[22] := k[21] + 2 * FH[2] * FH[4];
+  k[23] := 2 * FH[3] * FH[4];
+  k[24] := 2 * FH[0] * FH[1];
+  k[25] := FH[0] * FH[0];      // KILL?
+  k[26] := FH[5] * k[25];    // KILL?
+  k[126] := FH[5] * FH[0];
+  k[127] := FH[5] * FH[1] + FH[6] * FH[0];
+  k[128] := FH[6] * FH[1];
+  k[27] := FH[5] * k[24] + FH[6] * k[25];   // KILL?
+  k[28] := FH[1] * FH[1];                // KILL?
+  k[29] := FH[5] * k[28] + FH[6] * k[24];   // KILL?
+  k[30] := FH[6] * k[28];        // KILL?
+  k[31] := FH[2] * FH[2];
+  k[132] := k[20] + 4 * k[126];
+  k[133] := k[22] + 4 * k[127];
+  k[134] := k[23] + 4 * k[128];
+  k[32] := k[31] + 4 * k[26];      // KILL?
+  k[33] := k[20] + 4 * k[27];       // KILL?
+  k[34] := k[22] + 4 * k[29];      // KILL?
+  k[35] := k[23] + 4 * k[30];     // KILL?
+  k[36] := k[31] + 2 * k[26];    // KILL?
+  k[37] := k[20] + 2 * k[27];    // KILL?
+  k[38] := k[22] + 2 * k[29];    // KILL?
+  k[39] := k[23] + 2 * k[30];      // KILL?
+  k[137] := k[20] + 2 * k[126];
+  k[138] := k[22] + 2 * k[127];
+  k[139] := k[23] + 2 * k[128];
+  k[40] := k[14] + V_10 * (k[12] - k[9]);
+  k[41] := k[15] + V_10 * k[6];
+  k[42] := k[16] - k[14] - V_10 * k[13] - (k[12] - k[9]) * V_00;
+  k[43] := k[17] - k[15] + V_10 * k[19] - (k[12] - k[9]) * k[1] - k[6] * V_00;
+  k[44] := k[18] - k[6] * k[1];
+  k[45] := k[42] * FH[0] - k[40] * FH[2];
+  k[46] := k[42] * FH[1] + k[43] * FH[0] - k[41] * FH[2] - k[40] * FH[3];
+  k[47] := k[43] * FH[1] + k[44] * FH[0] - k[41] * FH[3] - k[40] * FH[4];
+  k[48] := k[44] * FH[1] - k[41] * FH[4];
+  k[49] := k[42] * FH[2];
+  k[50] := k[40] * k[31] - k[49] * FH[0];
+  k[51] := k[42] * FH[3] + k[43] * FH[2];
+  k[52] := k[40] * k[137] + k[41] * k[31] - k[51] * FH[0] - k[49] * FH[1];
+  k[53] := k[42] * FH[4] + k[43] * FH[3] + k[44] * FH[2];
+  k[54] := k[40] * k[138] + k[41] * k[137] - k[53] * FH[0] - k[51] * FH[1];
+  k[55] := k[43] * FH[4] + k[44] * FH[3];
+  k[56] := k[40] * k[139] + k[41] * k[138] - k[55] * FH[0] - k[53] * FH[1];
+  k[57] := k[44] * FH[4];
+  k[58] := FH[4] * FH[4];
+  k[59] := k[40] * k[58] + k[41] * k[139] - k[57] * FH[0] - k[55] * FH[1];
+  k[60] := k[41] * k[58] - k[57] * FH[1];
+  k[61] := k[13] * V_00 - k[16];
+  k[62] := 2 * k[25] * k[61];
+  k[63] := k[13] * k[1] - k[19] * V_00 - k[17];
+  k[64] := 2 * (k[24] * k[61] + k[25] * k[63]);
+  k[65] := - k[19] * k[1] - k[18];
+  k[66] := 2 * (k[28] * k[61] + k[24] * k[63] + k[25] * k[65]);
+  k[67] := 2 * (k[28] * k[63] + k[24] * k[65]);
+  k[68] := 2 * k[28] * k[65];
+  k[69] := k[50] + k[62];
+  k[70] := k[52] + k[64];
+  k[71] := k[54] + k[66];
+  k[72] := k[56] + k[67];
+  k[73] := k[59] + k[68];
+  k[74] := k[45] * k[45];
+  k[75] := 2 * k[45] * k[46];
+  k[76] := k[46] * k[46] + 2 * k[45] * k[47];
+  k[77] := 2 * (k[45] * k[48] + k[46] * k[47]);
+  k[78] := k[47] * k[47] + 2 * k[46] * k[48];
+  k[79] := 2 * k[47] * k[48];
+  k[80] := k[48] * k[48];
+
+  FA[0] := k[58] * k[80] - k[60] * k[60];
+  FA[1] := k[134] * k[80] + k[58] * k[79] - 2 * k[73] * k[60];
+  FA[2] := k[133] * k[80] + k[134] * k[79] + k[58] * k[78] - k[73] * k[73] - 2 * k[72] * k[60];
+  FA[3] := k[133] * k[79] + k[134] * k[78] + k[58] * k[77] + k[132] * k[80]
+    - 2 * (k[71] * k[60] + k[72] * k[73]);
+  FA[4] := k[31] * k[80] + k[133] * k[78] + k[134] * k[77] + k[58] * k[76] + k[132] * k[79] - k[72] * k[72]
+    - 2 * (k[70] * k[60] + k[71] * k[73]);
+  FA[5] := k[31] * k[79] + k[133] * k[77] + k[134] * k[76] + k[58] * k[75] + k[132] * k[78]
+    - 2 * (k[69] * k[60] + k[70] * k[73] + k[71] * k[72]);
+  FA[6] := k[31] * k[78] + k[133] * k[76] + k[134] * k[75] + k[58] * k[74] + k[132] * k[77] - k[71] * k[71]
+    - 2 * (k[69] * k[73] + k[70] * k[72]);
+  FA[7] := k[31] * k[77] + k[133] * k[75] + k[134] * k[74] + k[132] * k[76] - 2 * (k[69] * k[72] + k[70] * k[71]);
+  FA[8] := k[31] * k[76] + k[132] * k[75] + k[133] * k[74] - k[70] * k[70] - 2 * k[69] * k[71];
+  FA[9] := k[31] * k[75] + k[132] * k[74] - 2 * k[69] * k[70];
+  FA[10] := k[31] * k[74] - k[69] * k[69];
+
+  // Debug calculations
+  //a_1 := V_00 * t_0 + P_00 - P_20;
+  //a_2 := V_00 * t_0 + P_00 - P_10;
+  //b_0 := (P_11 - P_21) * t_0;
+  //b_1 := (V_01 - V_21) * t_0 + P_01 - P_11;
+  //c_0 := (V_01 - V_11) * t_0 + P_01 - P_21;
+  //c_1 := V_11 - V_21;
+  //d_0 := (P_22 - P_12) * t_0;
+  //d_1 := (V_02 - V_12) * t_0 + P_02 - P_22;
+  //e_0 := (V_02 - V_22) * t_0 + P_02 - P_12;
+  //e_1 := V_22 - V_12;
+  //f_2 := c_0 * e_1 + c_1 * d_1;
+  //f_1 := c_0 * e_0 + c_1 * d_0 - b_0 * e_1 - b_1 * d_1;
+  //f_0 := b_1 * d_0 + b_0 * e_0;
+  //
+  //act := f_2 * t_1 * t_1 + f_1 * t_1 - f_0;
+  //Write('debug10: ', 0 = act, '    ');
+  //
+  //if f_2 <> 0 then
+  //begin
+  //  act := Round(- f_1 / (2 * f_2) + Sqrt((f_1 / (2 * f_2)) * (f_1 / (2 * f_2)) + f_0 / f_2));
+  //  Write('debug15: ', t_1 = act);
+  //  act := Round(- f_1 / (2 * f_2) - Sqrt((f_1 / (2 * f_2)) * (f_1 / (2 * f_2)) + f_0 / f_2));
+  //  Write(' OR ', t_1 = act, '    ');
+  //end;
+  //
+  //act := (e_0 + e_1 * t_1) * t_2 - (d_0 + d_1 * t_1);
+  //Write('debug20: ', 0 = act, '    ');
+  //
+  //act := (a_1 * e_1 - V_20 * d_1 + V_10 * (d_1 - e_1 * t_0)) * t_1 * t_1
+  //  + (a_1 * e_0 - V_20 * d_0 - t_0 * (a_1 * e_1  - V_20 * d_1) - (d_1 - e_1 * t_0) * a_2 + V_10 * (d_0 - e_0 * t_0)) * t_1
+  //  + t_0 * (V_20 * d_0 - a_1 * e_0) + (e_0 * t_0 - d_0) * a_2;
+  //Write('debug30: ', 0 = act, '    ');
+  //
+  //act := Round((a_1 * e_1 - V_20 * d_1 + V_10 * (d_1 - e_1 * t_0)) * (f_1 * f_1 + 2 * f_0 * f_2 - f_1 * Sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+  //  + (a_1 * e_0 - V_20 * d_0 - t_0 * (a_1 * e_1 - V_20 * d_1) - (d_1 - e_1 * t_0) * a_2 + V_10 * (d_0 - e_0 * t_0)) * (- f_1 * f_2 + f_2 * Sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+  //  + t_0 * (V_20 * d_0 - a_1 * e_0) * 2 * f_2 * f_2 + (e_0 * t_0 - d_0) * a_2 * 2 * f_2 * f_2);
+  //Write('debug40: ', 0 = act, '    ');
+  //
+  //Write('debug41: ',
+  //  a_1 * k[9] - V_20 * d_1
+  //  = k[14] * t_0 + k[15], '    ');
+  //Write('debug42: ',
+  //  d_1 - k[9] * t_0
+  //  = (k[12] - k[9]) * t_0 + k[6], '    ');
+  //Write('debug43: ',
+  //  a_1 * e_0 - V_20 * d_0
+  //  = k[16] * t_0 * t_0 + k[17] * t_0 + k[18], '    ');
+  //Write('debug44: ',
+  //  d_0 - e_0 * t_0
+  //  = - k[13] * t_0 * t_0 + k[19] * t_0, '    ');
+  //Write('debug45: ',
+  //  f_1 * f_1
+  //  = FH[2] * FH[2] * t_0 * t_0 * t_0 * t_0 + k[20] * t_0 * t_0 * t_0 + k[22] * t_0 * t_0 + k[23] * t_0 + FH[4] * FH[4], '    ');
+  //Write('debug46: ',
+  //  f_2 * f_2
+  //  = FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1], '    ');
+  //Write('debug47: ',
+  //  f_0 * f_2
+  //  = k[126] * t_0 * t_0 * t_0 + k[127] * t_0 * t_0 + k[128] * t_0, '    ');
+  //Write('debug48: ',
+  //  f_1 * f_1 + 4 * f_0 * f_2
+  //  = k[31] * t_0 * t_0 * t_0 * t_0 + k[132] * t_0 * t_0 * t_0 + k[133] * t_0 * t_0 + k[134] * t_0 + k[58], '    ');
+  //Write('debug49: ',
+  //  f_1 * f_1 + 2 * f_0 * f_2
+  //  = k[31] * t_0 * t_0 * t_0 * t_0 + k[137] * t_0 * t_0 * t_0 + k[138] * t_0 * t_0 + k[139] * t_0 + k[58], '    ');
+  //
+  //act := Round((k[14] * t_0 + k[15] + V_10 * ((k[12] - k[9]) * t_0 + k[6])) * (k[31] * t_0 * t_0 * t_0 * t_0 + k[137] * t_0 * t_0 * t_0 + k[138] * t_0 * t_0 + k[139] * t_0 + k[58] - f_1 * sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+  //  + (k[16] * t_0 * t_0 + k[17] * t_0 + k[18] - t_0 * (k[14] * t_0 + k[15]) - ((k[12] - k[9]) * t_0 + k[6]) * a_2 - V_10 * (k[13] * t_0 * t_0 - k[19] * t_0)) * (- f_1 * f_2 + f_2 * sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+  //  - 2 * t_0 * (k[16] * t_0 * t_0 + k[17] * t_0 + k[18]) * (FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1]) + 2 * (k[13] * t_0 * t_0 - k[19] * t_0) * a_2 * (FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1]));
+  //Write('debug50: ', 0 = act, '    ');
+  //
+  //Write('debug53: ',
+  //  0 = Round((k[40] * t_0 + k[41]) * (k[31] * t_0 * t_0 * t_0 * t_0 + k[137] * t_0 * t_0 * t_0 + k[138] * t_0 * t_0 + k[139] * t_0 + k[58] - f_1 * sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+  //    + ((k[16] - k[14] - V_10 * k[13] - (k[12] - k[9]) * V_00) * t_0 * t_0 + (k[17] - k[15] + V_10 * k[19] - (k[12] - k[9]) * k[1] - k[6] * V_00) * t_0 + k[18] - k[6] * k[1]) * (- f_1 * f_2 + f_2 * sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+  //    - 2 * t_0 * (k[16] * t_0 * t_0 + k[17] * t_0 + k[18]) * (FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1]) + 2 * (k[13] * t_0 * t_0 - k[19] * t_0) * a_2 * (FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1])),
+  //    '    ');
+  //
+  //Write('debug55: ',
+  //  0 = Round((k[40] * t_0 + k[41]) * (k[31] * t_0 * t_0 * t_0 * t_0 + k[137] * t_0 * t_0 * t_0 + k[138] * t_0 * t_0 + k[139] * t_0 + k[58])
+  //    - (k[40] * t_0 + k[41]) * f_1 * sqrt(f_1 * f_1 + 4 * f_0 * f_2)
+  //    + (k[42] * t_0 * t_0 + k[43] * t_0 + k[44]) * (- f_1 * f_2 + f_2 * sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+  //    - 2 * t_0 * (k[16] * t_0 * t_0 + k[17] * t_0 + k[18]) * (FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1]) + 2 * (k[13] * t_0 * t_0 - k[19] * t_0) * a_2 * (FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1])),
+  //    '    ');
+  //
+  //Write('debug70: ',
+  //  0 = Round(((k[42] * t_0 * t_0 + k[43] * t_0 + k[44]) * (FH[0] * t_0 + FH[1]) - (k[40] * t_0 + k[41]) * (FH[2] * t_0 * t_0 + FH[3] * t_0 + FH[4])) * sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+  //    + (k[40] * t_0 + k[41]) * (k[31] * t_0 * t_0 * t_0 * t_0 + k[137] * t_0 * t_0 * t_0 + k[138] * t_0 * t_0 + k[139] * t_0 + k[58])
+  //    - (k[42] * t_0 * t_0 + k[43] * t_0 + k[44]) * (FH[2] * t_0 * t_0 + FH[3] * t_0 + FH[4]) * (FH[0] * t_0 + FH[1])
+  //    - 2 * t_0 * (k[16] * t_0 * t_0 + k[17] * t_0 + k[18]) * (FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1]) + 2 * (k[13] * t_0 * t_0 - k[19] * t_0) * (V_00 * t_0 + k[1]) * (FH[0] * FH[0] * t_0 * t_0 + k[24] * t_0 + FH[1] * FH[1]),
+  //    '    ');
+//
+//  Write('debug73: ',
+//    0 = Round((
+//        (k[42] * FH[0] - k[40] * FH[2]) * t_0 * t_0 * t_0
+//        + (k[42] * FH[1] + k[43] * FH[0] - k[41] * FH[2] - k[40] * FH[3]) * t_0 * t_0
+//        + (k[43] * FH[1] + k[44] * FH[0] - k[41] * FH[3] - k[40] * FH[4]) * t_0
+//        + k[44] * FH[1] - k[41] * FH[4]
+//    ) * sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+//    + (k[40] * k[31] - k[42] * FH[2] * FH[0]) * t_0 * t_0 * t_0 * t_0 * t_0
+//    + (k[40] * k[137] + k[41] * k[31] - k[42] * FH[3] * FH[0] - k[43] * FH[2] * FH[0] - k[42] * FH[2] * FH[1]) * t_0 * t_0 * t_0 * t_0
+//    + (k[40] * k[138] + k[41] * k[137] - k[42] * FH[4] * FH[0] - k[43] * FH[3] * FH[0] - k[44] * FH[2] * FH[0] - k[42] * FH[3] * FH[1] - k[43] * FH[2] * FH[1]) * t_0 * t_0 * t_0
+//    + (k[40] * k[139] + k[41] * k[138] - k[43] * FH[4] * FH[0] - k[44] * FH[3] * FH[0] - k[42] * FH[4] * FH[1] - k[43] * FH[3] * FH[1] - k[44] * FH[2] * FH[1]) * t_0 * t_0
+//    + (k[40] * k[58] + k[41] * k[139] - k[44] * FH[4] * FH[0] - k[43] * FH[4] * FH[1] - k[44] * FH[3] * FH[1]) * t_0
+//    + k[41] * k[58] - k[44] * FH[4] * FH[1]
+//    + 2 * (k[13] * V_00 * FH[0] * FH[0] - k[16] * FH[0] * FH[0]) * t_0 * t_0 * t_0 * t_0 * t_0
+//    + 2 * (k[13] * V_00 * k[24] + k[13] * k[1] * FH[0] * FH[0] - k[19] * V_00 * FH[0] * FH[0] - k[16] * k[24] - k[17] * FH[0] * FH[0]) * t_0 * t_0 * t_0 * t_0
+//    + 2 * (k[13] * V_00 * FH[1] * FH[1] + k[13] * k[1] * k[24] - k[19] * V_00 * k[24] - k[19] * k[1] * FH[0] * FH[0] - k[16] * FH[1] * FH[1] - k[17] * k[24] - k[18] * FH[0] * FH[0]) * t_0 * t_0 * t_0
+//    + 2 * (k[13] * k[1] * FH[1] * FH[1] - k[19] * V_00 * FH[1] * FH[1] - k[19] * k[1] * k[24] - k[17] * FH[1] * FH[1] - k[18] * k[24]) * t_0 * t_0
+//    + 2 * (- k[19] * k[1] * FH[1] * FH[1] - k[18] * FH[1] * FH[1]) * t_0,
+//    '    ');
+//
+//  Write('debug78: ',
+//    0 = Round((k[45] * t_0 * t_0 * t_0 + k[46] * t_0 * t_0 + k[47] * t_0 + k[48]) * sqrt(f_1 * f_1 + 4 * f_0 * f_2))
+//      + (k[50] + k[62]) * t_0 * t_0 * t_0 * t_0 * t_0 + (k[52] + k[64]) * t_0 * t_0 * t_0 * t_0 + (k[54] + k[66]) * t_0 * t_0 * t_0 + (k[56] + k[67]) * t_0 * t_0 + (k[59] + k[68]) * t_0 + k[60],
+//      '    ');
+//
+//  Write('debug80: ',
+//    0 = Round((k[45] * t_0 * t_0 * t_0 + k[46] * t_0 * t_0 + k[47] * t_0 + k[48]) * sqrt(k[31] * t_0 * t_0 * t_0 * t_0 + k[132] * t_0 * t_0 * t_0 + k[133] * t_0 * t_0 + k[134] * t_0 + k[58])
+//      + k[69] * t_0 * t_0 * t_0 * t_0 * t_0 + k[70] * t_0 * t_0 * t_0 * t_0 + k[71] * t_0 * t_0 * t_0 + k[72] * t_0 * t_0 + k[73] * t_0 + k[60]),
+//      '    ');
+//  WriteLn;
+//  WriteLn('  0 = ((', k[45], ') * x^3 + (', k[46], ') * x^2 + (', k[47], ') * x + (', k[48], ')) * sqrt((', k[31], ') * x^4 + (', k[132], ') * x^3 + (', k[133], ') * x^2 + (', k[134], ') * x + (', k[58], ')) + (',
+//    k[69], ') * x^5 + (', k[70], ') * x^4 + (', k[71], ') * x^3 + (', k[72], ') * x^2 + (', k[73], ') * x + (', k[60], ')');
+
+  Write('debug83: ',
+    (k[45] * t_0 * t_0 * t_0 + k[46] * t_0 * t_0 + k[47] * t_0 + k[48]) * (k[45] * t_0 * t_0 * t_0 + k[46] * t_0 * t_0 + k[47] * t_0 + k[48]) * (k[31] * t_0 * t_0 * t_0 * t_0 + k[132] * t_0 * t_0 * t_0 + k[133] * t_0 * t_0 + k[134] * t_0 + k[58]) =
+      (k[69] * t_0 * t_0 * t_0 * t_0 * t_0 + k[70] * t_0 * t_0 * t_0 * t_0 + k[71] * t_0 * t_0 * t_0 + k[72] * t_0 * t_0 + k[73] * t_0 + k[60]) * (k[69] * t_0 * t_0 * t_0 * t_0 * t_0 + k[70] * t_0 * t_0 * t_0 * t_0 + k[71] * t_0 * t_0 * t_0 + k[72] * t_0 * t_0 + k[73] * t_0 + k[60]),
+      '    ');
+  Write('debug85: ',
+    0 =
+      (
+          k[45] * k[45] * t_0 * t_0 * t_0 * t_0 * t_0 * t_0
+          + 2 * k[45] * k[46] * t_0 * t_0 * t_0 * t_0 * t_0
+          + k[46] * k[46] * t_0 * t_0 * t_0 * t_0
+          + 2 * k[45] * k[47] * t_0 * t_0 * t_0 * t_0
+          + 2 * k[45] * k[48] * t_0 * t_0 * t_0
+          + 2 * k[46] * k[47] * t_0 * t_0 * t_0
+          + k[47] * k[47] * t_0 * t_0
+          + 2 * k[46] * k[48] * t_0 * t_0
+          + 2 * k[47] * k[48] * t_0
+          + k[48] * k[48]
+      ) * (k[31] * t_0 * t_0 * t_0 * t_0 + k[132] * t_0 * t_0 * t_0 + k[133] * t_0 * t_0 + k[134] * t_0 + k[58])
+      - k[69] * k[69] * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0
+      - 2 * k[69] * k[70] * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0
+      - (k[70] * k[70] + 2 * k[69] * k[71]) * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0
+      - 2 * (k[69] * k[72] + k[70] * k[71]) * t_0 * t_0 * t_0 * t_0 * t_0 * t_0 * t_0
+      - (k[71] * k[71] + 2 * k[69] * k[73] + 2 * k[70] * k[72]) * t_0 * t_0 * t_0 * t_0 * t_0 * t_0
+      - 2 * (k[69] * k[60] + k[70] * k[73] + k[71] * k[72]) * t_0 * t_0 * t_0 * t_0 * t_0
+      - (k[72] * k[72] + 2 * k[70] * k[60] + 2 * k[71] * k[73]) * t_0 * t_0 * t_0 * t_0
+      - 2 * (k[71] * k[60] + k[72] * k[73]) * t_0 * t_0 * t_0
+      - (k[73] * k[73] + 2 * k[72] * k[60]) * t_0 * t_0
+      - 2 * k[73] * k[60] * t_0
+      - k[60] * k[60],
+      '    ');
+
+  WriteLn('debug96: ', EvaluateAt(t_0) = 0);
+
+  NormalizeCoefficients;
+
+  WriteLn('debug99: ', EvaluateAt(t_0) = 0, '    ');
+end;
+
+function TFirstCollisionPolynomial.EvaluateAt(const AT0: Int64): TBigInt;
+var
+  i: Low(FA)..High(FA);
+begin
+  Result := TBigInt.Zero;
+  for i := High(FA) downto Low(FA) do
+    Result := Result * AT0 + FA[i];
+end;
+
+function TFirstCollisionPolynomial.CalcPositiveIntegerRoot: Int64;
+var
+  dividers: TDividers;
+  factors: TInt64Array;
+  divider: Int64;
+begin
+  Result := 0;
+  //factors := TIntegerFactorization.PollardsRhoAlgorithm(FA[0]);
+  //dividers := TDividers.Create(factors);
+  //
+  //try
+  //for divider in dividers do
+  //begin
+  //  //WriteLn('Check if ', divider, ' is a root...');
+  //  if EvaluateAt(divider) = 0 then
+  //  begin
+  //    Result := divider;
+  //    Break;
+  //  end;
+  //end;
+  //
+  //finally
+  //  dividers.Free;
+  //end;
+end;
+
+function TFirstCollisionPolynomial.CalcT1(const AT0: Int64): Int64;
+var
+  g_0, g_1, g_2: Int64;
+  g: Extended;
+begin
+  //g_2 := FH[0] * AT0 + FH[1];
+  //g_1 := FH[2] * AT0 * AT0 + FH[3] * AT0 + FH[4];
+  //g_0 := FH[5] * AT0 * AT0 + FH[6] * AT0;
+  //g := - g_1 / (2 * g_2);
+  //Result := Round(g + sqrt(g * g + g_0));
+end;
+
 { TNeverTellMeTheOdds }
 
 function TNeverTellMeTheOdds.AreIntersecting(constref AHailstone1, AHailstone2: THailstone): Boolean;
@@ -60,58 +523,113 @@ var
   m1, m2, x, y: Double;
 begin
   Result := False;
-  m1 := AHailstone1.VY / AHailstone1.VX;
-  m2 := AHailstone2.VY / AHailstone2.VX;
+  m1 := AHailstone1.Velocity.data[1] / AHailstone1.Velocity.data[0];
+  m2 := AHailstone2.Velocity.data[1] / AHailstone2.Velocity.data[0];
   if m1 <> m2 then
   begin
-    x := (AHailstone2.Y - m2 * AHailstone2.X - AHailstone1.Y + m1 * AHailstone1.X) / (m1 - m2);
+    x := (AHailstone2.Position.data[1] - m2 * AHailstone2.Position.data[0]
+      - AHailstone1.Position.data[1] + m1 * AHailstone1.Position.data[0])
+      / (m1 - m2);
     if (FMin <= x) and (x <= FMax)
-    and (x * Sign(AHailstone1.VX) >= AHailstone1.X * Sign(AHailstone1.VX))
-    and (x * Sign(AHailstone2.VX) >= AHailstone2.X * Sign(AHailstone2.VX)) then
+    and (x * Sign(AHailstone1.Velocity.data[0]) >= AHailstone1.Position.data[0] * Sign(AHailstone1.Velocity.data[0]))
+    and (x * Sign(AHailstone2.Velocity.data[0]) >= AHailstone2.Position.data[0] * Sign(AHailstone2.Velocity.data[0]))
+    then
     begin
-      y := m1 * (x - AHailstone1.X) + AHailstone1.Y;
+      y := m1 * (x - AHailstone1.Position.data[0]) + AHailstone1.Position.data[1];
       if (FMin <= y) and (y <= FMax) then
         Result := True
     end;
   end;
 end;
 
+// For debug calculations:
+Const
+  T : array[0..4] of Byte = (5, 3, 4, 6, 1);
+
+procedure TNeverTellMeTheOdds.FindRockThrow(const AIndex1, AIndex2, AIndex3: Integer);
+var
+  //i, j, k: Integer;
+  //x0, x1, x2: Extended;
+  f: TFirstCollisionPolynomial;
+  t0, t1: Int64;
+  p, v: Tvector3_extended;
+  test: TBigInt;
+begin
+  WriteLn;
+  WriteLn(AIndex1, ' ', AIndex2, ' ', AIndex3);
+  f := TFirstCollisionPolynomial.Create;
+  f.Init(FHailstones[AIndex1], FHailstones[AIndex2], FHailstones[AIndex3], T[AIndex1], T[AIndex2], T[AIndex3]);
+  //t0 := f.CalcPositiveIntegerRoot;
+  //WriteLn('t0: ', t0, ' ', t0 = T[AIndex1]);
+  //t1 := f.CalcT1(t0);
+  //WriteLn(', t1: ', t1);
+  f.Free;
+
+  //// V_x = (V_0 * t_0 - V_1 * t_1 + P_0 - P_1) / (t_0 - t_1)
+  //v := (FHailstones[AIndex1].Velocity * t0 - FHailstones[AIndex2].Velocity * t1
+  //  + FHailstones[AIndex1].Position - FHailstones[AIndex2].Position) / (t0 - t1);
+  //// P_x = (V_0 - V_x) * t_0 + P_0
+  //p := (FHailstones[AIndex1].Velocity - v) * t0 + FHailstones[AIndex1].Position;
+  //FPart2 := Round(p.data[0]) + Round(p.data[1]) + Round(p.data[2]);
+
+  //for i := 0 to FHailstones.Count - 3 do
+  //  for j := i + 1 to FHailstones.Count - 2 do
+  //    for k:= j + 1 to FHailstones.Count - 1 do
+  //    begin
+  //      WriteLn(i, j, k);
+  //      solver := TRockThrowSolver.Create(FHailstones[i], FHailstones[j], FHailstones[k], 0);
+  //      case i of
+  //        0: x0 := 5;
+  //        1: x0 := 3;
+  //        2: x0 := 4;
+  //      end;
+  //      f := solver.CalcValue(x0);
+  //      solver.Free;
+  //    end;
+
+  //for i := 80 to 120 do
+  //begin
+  //  solver := TRockThrowSolver.Create(FHailstones[0], FHailstones[1], FHailstones[2], 0);
+  //  x0 := i / 20;
+  //  f := solver.CalcValue(x0);
+  //  WriteLn(x0, ' ', f.Valid, ' ', f.Value);
+  //  solver.Free;
+  //end;
+end;
+
 constructor TNeverTellMeTheOdds.Create(const AMin: Int64; const AMax: Int64);
 begin
   FMin := AMin;
   FMax := AMax;
-  FHailStones := THailstones.Create;
+  FHailstones := THailstones.Create;
 end;
 
 destructor TNeverTellMeTheOdds.Destroy;
 begin
-  FHailStones.Free;
+  FHailstones.Free;
   inherited Destroy;
 end;
 
 procedure TNeverTellMeTheOdds.ProcessDataLine(const ALine: string);
-var
-  split: TStringArray;
-  hailstone: THailstone;
 begin
-  split := ALine.Split([',', '@']);
-  hailstone.X := StrToInt64(Trim(split[0]));
-  hailstone.Y := StrToInt64(Trim(split[1]));
-  hailstone.Z := StrToInt64(Trim(split[2]));
-  hailstone.VX := StrToInt(Trim(split[3]));
-  hailstone.VY := StrToInt(Trim(split[4]));
-  hailstone.VZ := StrToInt(Trim(split[5]));
-  FHailStones.Add(hailstone);
+  FHailstones.Add(THailstone.Create(ALine));
 end;
 
 procedure TNeverTellMeTheOdds.Finish;
 var
-  i, j: Integer;
+  i, j, k: Integer;
 begin
-  for i := 0 to FHailStones.Count - 2 do
-    for j := i + 1 to FHailStones.Count - 1 do
-      if AreIntersecting(FHailStones[i], FHailStones[j]) then
+  for i := 0 to FHailstones.Count - 2 do
+    for j := i + 1 to FHailstones.Count - 1 do
+      if AreIntersecting(FHailstones[i], FHailstones[j]) then
         Inc(FPart1);
+
+  for i := 0 to FHailstones.Count - 1 do
+    for j := 0 to FHailstones.Count - 1 do
+      for k := 0 to FHailstones.Count - 1 do
+        if (i <> j) and (i <> k) and (j <> k) then
+          FindRockThrow(i, j, k);
+  //FindRockThrow(0, 1, 2);
 end;
 
 function TNeverTellMeTheOdds.GetDataFileName: string;
diff --git a/tests/UNeverTellMeTheOddsTestCases.pas b/tests/UNeverTellMeTheOddsTestCases.pas
index 8b5c282..a2f1235 100644
--- a/tests/UNeverTellMeTheOddsTestCases.pas
+++ b/tests/UNeverTellMeTheOddsTestCases.pas
@@ -33,6 +33,7 @@ type
     function CreateSolver: ISolver; override;
   published
     procedure TestPart1;
+    procedure TestPart2;
   end;
 
   { TNeverTellMeTheOddsExampleTestCase }
@@ -42,6 +43,7 @@ type
     function CreateSolver: ISolver; override;
   published
     procedure TestPart1;
+    procedure TestPart2;
   end;
 
   { TNeverTellMeTheOddsTestCase }
@@ -77,6 +79,11 @@ begin
   AssertEquals(15107, FSolver.GetResultPart1);
 end;
 
+procedure TNeverTellMeTheOddsFullDataTestCase.TestPart2;
+begin
+  AssertEquals(-1, FSolver.GetResultPart2);
+end;
+
 { TNeverTellMeTheOddsExampleTestCase }
 
 function TNeverTellMeTheOddsExampleTestCase.CreateSolver: ISolver;
@@ -89,6 +96,11 @@ begin
   AssertEquals(2, FSolver.GetResultPart1);
 end;
 
+procedure TNeverTellMeTheOddsExampleTestCase.TestPart2;
+begin
+  AssertEquals(47, FSolver.GetResultPart2);
+end;
+
 { TNeverTellMeTheOddsTestCase }
 
 function TNeverTellMeTheOddsTestCase.CreateSolver: ISolver;