diff --git a/AdventOfCode.lpi b/AdventOfCode.lpi index f9cc1bf..f3c814a 100644 --- a/AdventOfCode.lpi +++ b/AdventOfCode.lpi @@ -85,6 +85,10 @@ + + + + diff --git a/AdventOfCode.lpr b/AdventOfCode.lpr index 5d88d23..b355b57 100644 --- a/AdventOfCode.lpr +++ b/AdventOfCode.lpr @@ -26,7 +26,7 @@ uses Classes, SysUtils, CustApp, USolver, UTrebuchet, UCubeConundrum, UGearRatios, UScratchcards, UGiveSeedFertilizer, UWaitForIt, UCamelCards, - UHauntedWasteland, UNumberTheory, UMirageMaintenance, UPipeMaze, UCosmicExpansion, UHotSprings; + UHauntedWasteland, UNumberTheory, UMirageMaintenance, UPipeMaze, UCosmicExpansion, UHotSprings, UPointOfIncidence; type @@ -63,6 +63,7 @@ begin engine.RunAndFree(TPipeMaze.Create); engine.RunAndFree(TCosmicExpansion.Create); engine.RunAndFree(THotSprings.Create); + engine.RunAndFree(TPointOfIncidence.Create); engine.Free; end; diff --git a/solvers/UPointOfIncidence.pas b/solvers/UPointOfIncidence.pas new file mode 100644 index 0000000..b4e9777 --- /dev/null +++ b/solvers/UPointOfIncidence.pas @@ -0,0 +1,186 @@ +{ + Solutions to the Advent Of Code. + Copyright (C) 2023 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 + Foundation, either version 3 of the License, or (at your option) any later + version. + + This program is distributed in the hope that it will be useful, but WITHOUT + ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS + FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along with + this program. If not, see . +} + +unit UPointOfIncidence; + +{$mode ObjFPC}{$H+} + +interface + +uses + Classes, SysUtils, Generics.Collections, Math, USolver; + +type + + { TPointOfIncidence } + + TPointOfIncidence = class(TSolver) + private + FLines: TStringList; + FHorizontalMirrorCandidates, FVerticalMirrorCandidates: specialize TList; + procedure ProcessPatternLine(const ALine: string); + procedure VerifyHorizontalCandidates(const ANewLine: string); + procedure CheckForNewHorizontalCandidate(const ANewLine: string); + procedure VerifyVerticalCandidates(const ALine: string); + procedure InitializeNewVerticalCandidates(const AFirstLine: string); + procedure FinishPattern; + public + constructor Create; + destructor Destroy; override; + procedure ProcessDataLine(const ALine: string); override; + procedure Finish; override; + function GetDataFileName: string; override; + function GetPuzzleName: string; override; + end; + +implementation + +{ TPointOfIncidence } + +procedure TPointOfIncidence.ProcessPatternLine(const ALine: string); +begin + VerifyHorizontalCandidates(ALine); + CheckForNewHorizontalCandidate(ALine); + + if FLines.Count > 0 then + VerifyVerticalCandidates(ALine) + else + InitializeNewVerticalCandidates(ALine); + + FLines.Add(ALine); +end; + +procedure TPointOfIncidence.VerifyHorizontalCandidates(const ANewLine: string); +var + i, mirroredIndex: Integer; +begin + // Checks if the current line fulfills the exisiting horizontal mirror candidates. + i := FHorizontalMirrorCandidates.Count - 1; + while i >= 0 do + begin + // Calculates the index of the line that the current line would be a duplicate of in regards to the i-th candidate. + mirroredIndex := 2 * FHorizontalMirrorCandidates[i] - FLines.Count - 1; + if (mirroredIndex >= 0) and (ANewLine <> FLines[mirroredIndex]) then + FHorizontalMirrorCandidates.Delete(i); + Dec(i); + end; +end; + +procedure TPointOfIncidence.CheckForNewHorizontalCandidate(const ANewLine: string); +begin + // Checks for new horizontal mirror candidate between ALine and the previous line. + if (FLines.Count > 0) and (ANewLine = FLines[FLines.Count - 1]) then + FHorizontalMirrorCandidates.Add(FLines.Count); +end; + +procedure TPointOfIncidence.VerifyVerticalCandidates(const ALine: string); +var + i, j, len, mirror: Integer; +begin + // Checks if the current line fulfills the exisiting vertical mirror candidates. + len := Length(ALine); + i := FVerticalMirrorCandidates.Count - 1; + while i >= 0 do + begin + mirror := FVerticalMirrorCandidates[i]; + for j := 0 to Min(mirror - 1, len - mirror - 1) do + begin + if ALine[mirror - j] <> ALine[mirror + j + 1] then + begin + FVerticalMirrorCandidates.Delete(i); + Break; + end; + end; + Dec(i); + end; +end; + +procedure TPointOfIncidence.InitializeNewVerticalCandidates(const AFirstLine: string); +var + i, j, len: Integer; + isMirror: Boolean; +begin + // Checks the line for vertical mirror candidates, i.e. mirrors that work for this line. + len := Length(AFirstLine); + for i := 1 to len - 1 do begin + isMirror := True; + for j := 0 to Min(i - 1, len - i - 1) do + begin + if AFirstLine[i - j] <> AFirstLine[i + j + 1] then + begin + isMirror := False; + Break; + end; + end; + if isMirror then + FVerticalMirrorCandidates.Add(i); + end; +end; + +procedure TPointOfIncidence.FinishPattern; +var + i: Integer; +begin + for i := 0 to FHorizontalMirrorCandidates.Count - 1 do + Inc(FPart1, FHorizontalMirrorCandidates[i] * 100); + for i := 0 to FVerticalMirrorCandidates.Count - 1 do + Inc(FPart1, FVerticalMirrorCandidates[i]); + FLines.Clear; + FHorizontalMirrorCandidates.Clear; + FVerticalMirrorCandidates.Clear; +end; + +constructor TPointOfIncidence.Create; +begin + FLines := TStringList.Create; + FHorizontalMirrorCandidates := specialize TList.Create; + FVerticalMirrorCandidates := specialize TList.Create; +end; + +destructor TPointOfIncidence.Destroy; +begin + FLines.Free; + FHorizontalMirrorCandidates.Free; + FVerticalMirrorCandidates.Free; + inherited Destroy; +end; + +procedure TPointOfIncidence.ProcessDataLine(const ALine: string); +begin + if ALine <> '' then + ProcessPatternLine(ALine) + else + FinishPattern; +end; + +procedure TPointOfIncidence.Finish; +begin + FinishPattern; +end; + +function TPointOfIncidence.GetDataFileName: string; +begin + Result := 'point_of_incidence.txt'; +end; + +function TPointOfIncidence.GetPuzzleName: string; +begin + Result := 'Day 13: Point of Incidence'; +end; + +end. + diff --git a/tests/AdventOfCodeFPCUnit.lpi b/tests/AdventOfCodeFPCUnit.lpi index 178fda6..9282724 100644 --- a/tests/AdventOfCodeFPCUnit.lpi +++ b/tests/AdventOfCodeFPCUnit.lpi @@ -92,6 +92,10 @@ + + + + diff --git a/tests/AdventOfCodeFPCUnit.lpr b/tests/AdventOfCodeFPCUnit.lpr index 896d2ac..ecd15fb 100644 --- a/tests/AdventOfCodeFPCUnit.lpr +++ b/tests/AdventOfCodeFPCUnit.lpr @@ -6,7 +6,7 @@ uses Interfaces, Forms, GuiTestRunner, USolver, UBaseTestCases, UTrebuchetTestCases, UCubeConundrumTestCases, UGearRatiosTestCases, UScratchcardsTestCases, UGiveSeedFertilizerTestCases, UWaitForItTestCases, UCamelCardsTestCases, UHauntedWastelandTestCases, UMirageMaintenanceTestCases, UPipeMazeTestCases, UCosmicExpansionTestCases, - UHotSpringsTestCases; + UHotSpringsTestCases, UPointOfIncidenceTestCases; {$R *.res} diff --git a/tests/UPointOfIncidenceTestCases.pas b/tests/UPointOfIncidenceTestCases.pas new file mode 100644 index 0000000..afc44dd --- /dev/null +++ b/tests/UPointOfIncidenceTestCases.pas @@ -0,0 +1,78 @@ +{ + Solutions to the Advent Of Code. + Copyright (C) 2023 Stefan Müller + + This program is free software: you can redistribute it and/or modify it under + the terms of the GNU General Public License as published by the Free Software + Foundation, either version 3 of the License, or (at your option) any later + version. + + This program is distributed in the hope that it will be useful, but WITHOUT + ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS + FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along with + this program. If not, see . +} + +unit UPointOfIncidenceTestCases; + +{$mode ObjFPC}{$H+} + +interface + +uses + Classes, SysUtils, fpcunit, testregistry, USolver, UBaseTestCases, UPointOfIncidence; + +type + + { TPointOfIncidenceFullDataTestCase } + + TPointOfIncidenceFullDataTestCase = class(TEngineBaseTest) + protected + function CreateSolver: ISolver; override; + published + procedure TestPart1; + end; + + { TPointOfIncidenceExampleTestCase } + + TPointOfIncidenceExampleTestCase = class(TExampleEngineBaseTest) + protected + function CreateSolver: ISolver; override; + published + procedure TestPart1; + end; + +implementation + +{ TPointOfIncidenceFullDataTestCase } + +function TPointOfIncidenceFullDataTestCase.CreateSolver: ISolver; +begin + Result := TPointOfIncidence.Create; +end; + +procedure TPointOfIncidenceFullDataTestCase.TestPart1; +begin + AssertEquals(37718, FSolver.GetResultPart1); +end; + +{ TPointOfIncidenceExampleTestCase } + +function TPointOfIncidenceExampleTestCase.CreateSolver: ISolver; +begin + Result := TPointOfIncidence.Create; +end; + +procedure TPointOfIncidenceExampleTestCase.TestPart1; +begin + AssertEquals(405, FSolver.GetResultPart1); +end; + +initialization + + RegisterTest(TPointOfIncidenceFullDataTestCase); + RegisterTest(TPointOfIncidenceExampleTestCase); +end. +