diff --git a/AdventOfCode2024.sln b/AdventOfCode2024.sln index e3e421e..96318ae 100644 --- a/AdventOfCode2024.sln +++ b/AdventOfCode2024.sln @@ -17,6 +17,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Day6", "Day6\Day6.csproj", EndProject Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Day7", "Day7\Day7.csproj", "{D177FD38-032B-4053-8E84-38368F74CBCE}" EndProject +Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Day8", "Day8\Day8.csproj", "{4D1D9998-BA7C-44F9-8305-DBB066485BAF}" +EndProject Global GlobalSection(SolutionConfigurationPlatforms) = preSolution Debug|Any CPU = Debug|Any CPU @@ -51,6 +53,10 @@ Global {D177FD38-032B-4053-8E84-38368F74CBCE}.Debug|Any CPU.Build.0 = Debug|Any CPU {D177FD38-032B-4053-8E84-38368F74CBCE}.Release|Any CPU.ActiveCfg = Release|Any CPU {D177FD38-032B-4053-8E84-38368F74CBCE}.Release|Any CPU.Build.0 = Release|Any CPU + {4D1D9998-BA7C-44F9-8305-DBB066485BAF}.Debug|Any CPU.ActiveCfg = Debug|Any CPU + {4D1D9998-BA7C-44F9-8305-DBB066485BAF}.Debug|Any CPU.Build.0 = Debug|Any CPU + {4D1D9998-BA7C-44F9-8305-DBB066485BAF}.Release|Any CPU.ActiveCfg = Release|Any CPU + {4D1D9998-BA7C-44F9-8305-DBB066485BAF}.Release|Any CPU.Build.0 = Release|Any CPU EndGlobalSection GlobalSection(SolutionProperties) = preSolution HideSolutionNode = FALSE diff --git a/Day8/Day8.csproj b/Day8/Day8.csproj new file mode 100644 index 0000000..e0c4c2e --- /dev/null +++ b/Day8/Day8.csproj @@ -0,0 +1,16 @@ + + + + Exe + net8.0 + enable + enable + + + + + Always + + + + diff --git a/Day8/Program.cs b/Day8/Program.cs new file mode 100644 index 0000000..27a8ecd --- /dev/null +++ b/Day8/Program.cs @@ -0,0 +1,196 @@ +var lines = File.ReadAllLines("input.txt"); +var charArray = new char[lines.Length, lines[0].Length]; + +for (var i = 0; i < charArray.GetLength(0); i++) + for (var j = 0; j < charArray.GetLength(1); j++) + { + charArray[i, j] = lines[i][j]; + } + +var uniqueCharacterPositions = GroupUniqueCharacterPositions(charArray); + +var antinodeLocations = new List<(int, int)>(); +var antinodeHarmonicsLocations = new List<(int, int)>(); + +foreach (var uniqueCharacter in uniqueCharacterPositions) +{ + for (var i = 0; i < uniqueCharacter.Value.Count - 1; i++) + { + var currentPosition = uniqueCharacter.Value[i]; + + for (var j = i + 1; j < uniqueCharacter.Value.Count; j++) + { + var nextPosition = uniqueCharacter.Value[j]; + + if (Distance(currentPosition.Item1, currentPosition.Item2, nextPosition.Item1, nextPosition.Item2) >= 1) + { + antinodeLocations.AddRange(CalculateAntinodes(currentPosition, nextPosition, charArray)); + } + + antinodeHarmonicsLocations.AddRange(CalculateAntinodesWithHarmonics(currentPosition, nextPosition, charArray)); + } + } +} + +Console.WriteLine( + $"Part 1: {antinodeLocations.Distinct().Count()}\nPart 2: {antinodeHarmonicsLocations.Distinct().Count()}"); + +List<(int, int)> CalculateAntinodesWithHarmonics((int, int) currentPosition, (int, int) nextPosition, char[,] input) +{ + var locations = new List<(int, int)> + { + currentPosition, + nextPosition + }; + + var verticalDistance = Math.Abs(currentPosition.Item1 - nextPosition.Item1); + var horizontalDistance = Math.Abs(currentPosition.Item2 - nextPosition.Item2); + + var currentPositionClone = currentPosition; + var nextPositionClone = nextPosition; + int antinodePositionRow, antinodePositionColumn; + + while (true) + { + if (currentPositionClone.Item1 < nextPositionClone.Item1) + { + antinodePositionRow = currentPositionClone.Item1 - verticalDistance; + } + else + { + antinodePositionRow = currentPositionClone.Item1 + verticalDistance; + } + + if (currentPositionClone.Item2 < nextPositionClone.Item2) + { + antinodePositionColumn = currentPositionClone.Item2 - horizontalDistance; + } + else + { + antinodePositionColumn = currentPositionClone.Item2 + horizontalDistance; + } + + if (IsValid(antinodePositionRow, antinodePositionColumn, input)) + { + locations.Add((antinodePositionRow, antinodePositionColumn)); + nextPositionClone = currentPositionClone; + currentPositionClone = (antinodePositionRow, antinodePositionColumn); + } + else + { + break; + } + } + + currentPositionClone = currentPosition; + nextPositionClone = nextPosition; + + while (true) + { + if (currentPositionClone.Item1 < nextPositionClone.Item1) + { + antinodePositionRow = nextPositionClone.Item1 + verticalDistance; + } + else + { + antinodePositionRow = nextPositionClone.Item1 - verticalDistance; + } + + if (currentPositionClone.Item2 < nextPositionClone.Item2) + { + antinodePositionColumn = nextPositionClone.Item2 + horizontalDistance; + } + else + { + antinodePositionColumn = nextPositionClone.Item2 - horizontalDistance; + } + + if (IsValid(antinodePositionRow, antinodePositionColumn, input)) + { + locations.Add((antinodePositionRow, antinodePositionColumn)); + currentPositionClone = nextPositionClone; + nextPositionClone = (antinodePositionRow, antinodePositionColumn); + } + else + { + break; + } + } + + return locations; +} + +List<(int, int)> CalculateAntinodes((int, int) currentPosition, (int, int) nextPosition, char[,] input) +{ + var locations = new List<(int, int)>(); + + int firstAntinodePositionRow, + firstAntinodePositionColumn, + secondAntinodePositionRow, + secondAntinodePositionColumn; + + var verticalDistance = Math.Abs(currentPosition.Item1 - nextPosition.Item1); + var horizontalDistance = Math.Abs(currentPosition.Item2 - nextPosition.Item2); + + if (currentPosition.Item1 < nextPosition.Item1) + { + firstAntinodePositionRow = currentPosition.Item1 - verticalDistance; + secondAntinodePositionRow = nextPosition.Item1 + verticalDistance; + } + else + { + firstAntinodePositionRow = currentPosition.Item1 + verticalDistance; + secondAntinodePositionRow = nextPosition.Item1 - verticalDistance; + } + + if (currentPosition.Item2 < nextPosition.Item2) + { + firstAntinodePositionColumn = currentPosition.Item2 - horizontalDistance; + secondAntinodePositionColumn = nextPosition.Item2 + horizontalDistance; + } + else + { + firstAntinodePositionColumn = currentPosition.Item2 + horizontalDistance; + secondAntinodePositionColumn = nextPosition.Item2 - horizontalDistance; + } + + if (IsValid(firstAntinodePositionRow, firstAntinodePositionColumn, input)) + { + locations.Add((firstAntinodePositionRow, firstAntinodePositionColumn)); + } + + if (IsValid(secondAntinodePositionRow, secondAntinodePositionColumn, input)) + { + locations.Add((secondAntinodePositionRow, secondAntinodePositionColumn)); + } + + return locations; +} + +Dictionary> GroupUniqueCharacterPositions(char[,] array) +{ + var charLocations = new Dictionary>(); + + for (var i = 0; i < array.GetLength(0); i++) + { + for (var j = 0; j < array.GetLength(1); j++) + { + var currentChar = array[i, j]; + + if (currentChar == '.') continue; + + if (!charLocations.ContainsKey(currentChar)) + { + charLocations[currentChar] = new List<(int, int)>(); + } + + charLocations[currentChar].Add((i, j)); + } + } + + return charLocations; +} + +bool IsValid(int row, int column, char[,] grid) => row >= 0 && row < grid.GetLength(0) && column >= 0 && column < grid.GetLength(1); + +double Distance(int position1Row, int position1Column, int position2Row, int position2Column) => Math.Sqrt(Math.Pow(position1Column - position2Column, 2) + Math.Pow(position2Row - position1Row, 2)); \ No newline at end of file diff --git a/Day8/input.txt b/Day8/input.txt new file mode 100644 index 0000000..b19f65d --- /dev/null +++ b/Day8/input.txt @@ -0,0 +1,50 @@ +..........K........................A.............. +.K................................A............... +......................................D.....A..... +....................................6............D +.................................................. +.............................d.................... +.........4.e.......................DT.B........... +....................d.....D......A...........B.... +.............K.................................... +...........................k...................... +...w..............4.....................y......... +........w......................................... +..............g..k..............d..........y...... +.....w.....Q..............................T....... +...............b..........k................6...... +.................................W...T............ +................w..............BW..T.............. +............g....4e.....................W......... +.......1.................g.......................W +........k..........................6.....0........ +.................a................................ +....................4.a........3.g..............7. +.............m........................I.0......... +..............K7..............V................... +....Q................................I............ +..9........b......................I............... +...................d.............................. +.......e.......................................... +....e...........t..E................3............. +......1..aQ........t....v.....3..........I..0..... +...........................v.t.....3.7............ +..........i.......m........M...................... +...Q..29..a...................m................... +...9......q..........mt........................... +....1...............Y.....M.........7............. +..........b..1...E.v..Y........................... +................v..........q...............0...... +..................E.................5............. +9...i..2b................................8........ +.....q..2............Y..M......................... +............q...............................V..... +...i.................................V............ +.i..............E............M.................... +.........................................G........ +............8................Y.................... +.........2................8..............5........ +......................................5....V...... +............................................G..... +.....................................5...........G +.................................8................ \ No newline at end of file