diff --git a/AdventOfCode.lpi b/AdventOfCode.lpi
index c8fe206..ac855eb 100644
--- a/AdventOfCode.lpi
+++ b/AdventOfCode.lpi
@@ -61,6 +61,10 @@
+
+
+
+
diff --git a/AdventOfCode.lpr b/AdventOfCode.lpr
index 306c507..4d5448f 100644
--- a/AdventOfCode.lpr
+++ b/AdventOfCode.lpr
@@ -25,7 +25,8 @@ uses
{$ENDIF}
Classes, SysUtils, CustApp,
USolver,
- UTrebuchet, UCubeConundrum, UGearRatios, UScratchcards, UGiveSeedFertilizer, UWaitForIt, UCamelCards;
+ UTrebuchet, UCubeConundrum, UGearRatios, UScratchcards, UGiveSeedFertilizer, UWaitForIt, UCamelCards,
+ UHauntedWasteland;
type
@@ -57,6 +58,7 @@ begin
engine.RunAndFree(TGiveSeedFertilizer.Create);
engine.RunAndFree(TWaitForIt.Create);
engine.RunAndFree(TCamelCards.Create);
+ engine.RunAndFree(THauntedWasteland.Create);
engine.Free;
end;
diff --git a/solvers/UHauntedWasteland.pas b/solvers/UHauntedWasteland.pas
new file mode 100644
index 0000000..97d611c
--- /dev/null
+++ b/solvers/UHauntedWasteland.pas
@@ -0,0 +1,239 @@
+{
+ Solutions to the Advent Of Code.
+ Copyright (C) 2023 Stefan Müller
+
+ This program is free software: you can redistribute it and/or modify it under
+ the terms of the GNU General Public License as published by the Free Software
+ Foundation, either version 3 of the License, or (at your option) any later
+ version.
+
+ This program is distributed in the hope that it will be useful, but WITHOUT
+ ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ this program. If not, see .
+}
+
+unit UHauntedWasteland;
+
+{$mode ObjFPC}{$H+}
+
+interface
+
+uses
+ Classes, SysUtils, Generics.Collections, USolver;
+
+type
+
+ { TNode }
+
+ TNode = class
+ private
+ FName: string;
+ FLeft, FRight: TNode;
+ public
+ constructor Create(const AName: string);
+ property Name: string read FName;
+ procedure AddNeighbors(constref ALeft, ARight: TNode);
+ function TryStep(const ADirection: Char; out ONewLocation: TNode): Boolean;
+ end;
+
+ TNodes = specialize TObjectList;
+
+ { THauntedWasteland }
+
+ THauntedWasteland = class(TSolver)
+ private
+ FDirections: string;
+ FNextDirectionIndex: Integer;
+ FNodes, FUnparsedNodes: TNodes;
+ FCurrentNode, FTargetNode: TNode;
+ procedure ProcessNode(const ALine: string);
+ procedure DoSteps;
+ 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
+
+{ TNode }
+
+constructor TNode.Create(const AName: string);
+begin
+ FName := AName;
+ FLeft := nil;
+ FRight := nil;
+end;
+
+procedure TNode.AddNeighbors(constref ALeft, ARight: TNode);
+begin
+ FLeft := ALeft;
+ FRight := ARight;
+end;
+
+function TNode.TryStep(const ADirection: Char; out ONewLocation: TNode): Boolean;
+begin
+ ONewLocation := nil;
+ Result := False;
+ case ADirection of
+ 'L':
+ if FLeft <> nil then
+ begin
+ ONewLocation := FLeft;
+ Result := True;
+ end;
+ 'R':
+ if FRight <> nil then
+ begin
+ ONewLocation := FRight;
+ Result := True;
+ end;
+ end;
+end;
+
+{ THauntedWasteland }
+
+procedure THauntedWasteland.ProcessNode(const ALine: string);
+var
+ name, left, right: string;
+ i: Integer;
+ parsingNode, leftNode, rightNode: TNode;
+begin
+ name := LeftStr(ALine, 3);
+ left := Copy(ALine, 8, 3);
+ right := Copy(ALine, 13, 3);
+
+ // Tries to find the new node in unparsed nodes.
+ i := 0;
+ parsingNode := nil;
+ while (parsingNode = nil) and (i < FUnparsedNodes.Count) do
+ begin
+ if FUnparsedNodes[i].Name = name then
+ begin
+ // New node was already encountered and is now parsed.
+ parsingNode := FUnparsedNodes[i];
+ FUnparsedNodes.Delete(i);
+ end;
+ Inc(i);
+ end;
+
+ // Adds new node to list of all nodes. We do this before looking for leftNode and rightNode because the node might
+ // reference itself.
+ if parsingNode = nil then
+ begin
+ parsingNode := TNode.Create(name);
+ FNodes.Add(parsingNode);
+ end;
+
+ // Tries to find leftNode and rightNode.
+ i := 0;
+ leftNode := nil;
+ rightNode := nil;
+ while ((leftNode = nil) or (rightNode = nil)) and (i < FNodes.Count) do
+ begin
+ if (leftNode = nil) and (FNodes[i].Name = left) then
+ begin
+ leftNode := FNodes[i];
+ end;
+ if (rightNode = nil) and (FNodes[i].Name = right) then
+ begin
+ rightNode := FNodes[i];
+ end;
+ Inc(i);
+ end;
+
+ // Adds leftNode and/or rightNode to list of all nodes and unparsed nodes.
+ if leftNode = nil then
+ begin
+ leftNode := TNode.Create(left);
+ FNodes.Add(leftNode);
+ FUnparsedNodes.Add(leftNode);
+ end;
+ if rightNode = nil then
+ begin
+ if right = left then
+ // This happens only if both left and right nodes are new.
+ rightNode := leftNode
+ else begin
+ rightNode := TNode.Create(right);
+ FNodes.Add(rightNode);
+ FUnparsedNodes.Add(rightNode);
+ end;
+ end;
+
+ parsingNode.AddNeighbors(leftNode, rightNode);
+
+ // Checks for start and end nodes.
+ if name = 'ZZZ' then
+ FTargetNode := parsingNode
+ else if name = 'AAA' then
+ FCurrentNode := parsingNode;
+end;
+
+procedure THauntedWasteland.DoSteps;
+var
+ new: TNode;
+begin
+ if FCurrentNode <> nil then
+ begin
+ while (FCurrentNode <> FTargetNode) and FCurrentNode.TryStep(FDirections[FNextDirectionIndex], new) do
+ begin
+ FCurrentNode := new;
+ Inc(FNextDirectionIndex);
+ if FNextDirectionIndex > Length(FDirections) then
+ FNextDirectionIndex := 1;
+ Inc(FPart1);
+ end;
+ end;
+end;
+
+constructor THauntedWasteland.Create;
+begin
+ FNextDirectionIndex := 1;
+ FNodes := TNodes.Create;
+ FUnparsedNodes := TNodes.Create(False);
+ FCurrentNode := nil;
+ FTargetNode := nil;
+end;
+
+destructor THauntedWasteland.Destroy;
+begin
+ FNodes.Free;
+ FUnparsedNodes.Free;
+ inherited Destroy;
+end;
+
+procedure THauntedWasteland.ProcessDataLine(const ALine: string);
+begin
+ if FDirections = '' then
+ FDirections := ALine
+ else if (ALine <> '') and ((FTargetNode = nil) or (FCurrentNode <> FTargetNode)) then
+ begin
+ ProcessNode(ALine);
+ DoSteps;
+ end;
+end;
+
+procedure THauntedWasteland.Finish;
+begin
+
+end;
+
+function THauntedWasteland.GetDataFileName: string;
+begin
+ Result := 'haunted_wasteland.txt';
+end;
+
+function THauntedWasteland.GetPuzzleName: string;
+begin
+ Result := 'Day 8: Haunted Wasteland';
+end;
+
+end.
+
diff --git a/tests/AdventOfCodeFPCUnit.lpi b/tests/AdventOfCodeFPCUnit.lpi
index c3472c8..597e381 100644
--- a/tests/AdventOfCodeFPCUnit.lpi
+++ b/tests/AdventOfCodeFPCUnit.lpi
@@ -72,6 +72,10 @@
+
+
+
+
diff --git a/tests/AdventOfCodeFPCUnit.lpr b/tests/AdventOfCodeFPCUnit.lpr
index 5601cc9..7554d8e 100644
--- a/tests/AdventOfCodeFPCUnit.lpr
+++ b/tests/AdventOfCodeFPCUnit.lpr
@@ -4,7 +4,8 @@ program AdventOfCodeFPCUnit;
uses
Interfaces, Forms, GuiTestRunner, USolver, UBaseTestCases, UTrebuchetTestCases, UCubeConundrumTestCases,
- UGearRatiosTestCases, UScratchcardsTestCases, UGiveSeedFertilizerTestCases, UWaitForItTestCases, UCamelCardsTestCases;
+ UGearRatiosTestCases, UScratchcardsTestCases, UGiveSeedFertilizerTestCases, UWaitForItTestCases, UCamelCardsTestCases,
+ UHauntedWastelandTestCases;
{$R *.res}
diff --git a/tests/UHauntedWastelandTestCases.pas b/tests/UHauntedWastelandTestCases.pas
new file mode 100644
index 0000000..01fa5ba
--- /dev/null
+++ b/tests/UHauntedWastelandTestCases.pas
@@ -0,0 +1,112 @@
+{
+ 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 UHauntedWastelandTestCases;
+
+{$mode ObjFPC}{$H+}
+
+interface
+
+uses
+ Classes, SysUtils, fpcunit, testregistry, USolver, UBaseTestCases, UHauntedWasteland;
+
+type
+
+ { THauntedWastelandFullDataTestCase }
+
+ THauntedWastelandFullDataTestCase = class(TEngineBaseTest)
+ protected
+ function CreateSolver: ISolver; override;
+ published
+ procedure TestPart1;
+ end;
+
+ { THauntedWastelandExampleTestCase }
+
+ THauntedWastelandExampleTestCase = class(TExampleEngineBaseTest)
+ protected
+ function CreateSolver: ISolver; override;
+ published
+ procedure TestPart1;
+ end;
+
+ { TExample2HauntedWasteland }
+
+ TExample2HauntedWasteland = class(THauntedWasteland)
+ function GetDataFileName: string; override;
+ end;
+
+ { THauntedWastelandExample2TestCase }
+
+ THauntedWastelandExample2TestCase = class(TExampleEngineBaseTest)
+ protected
+ function CreateSolver: ISolver; override;
+ published
+ procedure TestPart1;
+ end;
+
+implementation
+
+{ THauntedWastelandFullDataTestCase }
+
+function THauntedWastelandFullDataTestCase.CreateSolver: ISolver;
+begin
+ Result := THauntedWasteland.Create;
+end;
+
+procedure THauntedWastelandFullDataTestCase.TestPart1;
+begin
+ AssertEquals(14257, FSolver.GetResultPart1);
+end;
+
+{ THauntedWastelandExampleTestCase }
+
+function THauntedWastelandExampleTestCase.CreateSolver: ISolver;
+begin
+ Result := THauntedWasteland.Create;
+end;
+
+procedure THauntedWastelandExampleTestCase.TestPart1;
+begin
+ AssertEquals(2, FSolver.GetResultPart1);
+end;
+
+{ TExample2HauntedWasteland }
+
+function TExample2HauntedWasteland.GetDataFileName: string;
+begin
+ Result := 'haunted_wasteland2.txt';
+end;
+
+{ THauntedWastelandExample2TestCase }
+
+function THauntedWastelandExample2TestCase.CreateSolver: ISolver;
+begin
+ Result := TExample2HauntedWasteland.Create;
+end;
+
+procedure THauntedWastelandExample2TestCase.TestPart1;
+begin
+ AssertEquals(6, FSolver.GetResultPart1);
+end;
+
+initialization
+
+ RegisterTest(THauntedWastelandFullDataTestCase);
+ RegisterTest(THauntedWastelandExampleTestCase);
+ RegisterTest(THauntedWastelandExample2TestCase);
+end.