Add day 6, part 2 WIP

include/aoc/GridPathData.hpp

@@ -0,0 +1,25 @@
+// Solutions to the Advent Of Code 2024.
+// Copyright (C) 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
+// 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 <http://www.gnu.org/licenses/>.
+
+#pragma once
+
+#include <bitset>
+
+class GridPathData
+{
+public:
+    bool isVisited{ false };
+    std::bitset<4> isLoopingInDirection{ 0 };
+};

include/aoc/GuardGallivant.hpp

@@ -15,7 +15,12 @@
 
 #pragma once
 
+#include <vector>
+
+#include <aoc/Grid.hpp>
+#include <aoc/GridPathData.hpp>
 #include <aoc/LinesSolver.hpp>
+#include <aoc/Point2.hpp>
 
 class GuardGallivant
     : public LinesSolver
@@ -29,8 +34,12 @@ class GuardGallivant
     Point2 start_{};
     const size_t getStartDirectionIndex() const;
     const char getStartChar() const;
-    const char getVisitedChar() const;
     const char getObstructionChar() const;
-    void visitPosition(const Point2& current);
-    size_t turnDirection(const size_t current) const;
+    void tracePath();
+    void visitPosition(const Point2& current, const size_t directionIndex, Grid<GridPathData>& pathGrid);
+    void backtracePath(const Point2& current, const size_t directionIndex, Grid<GridPathData>& pathGrid);
+    void backtraceTurn(const Point2& current, const size_t reverseTurnDirectionIndex, Grid<GridPathData>& pathGrid);
+    size_t turnDirectionRight(const size_t currentDirectionIndex) const;
+    size_t turnDirectionLeft(const size_t currentDirectionIndex) const;
+    size_t revertDirection(const size_t currentDirectionIndex) const;
 };

include/aoc/Point2.hpp

@@ -15,6 +15,8 @@
 
 #pragma once
 
+#include <iostream>
+
 class Point2
 {
 public:
@@ -42,3 +44,5 @@ class Point2
     Point2& operator-=(const Point2& rhs);
     Point2& operator*=(const int rhs);
 };
+
+std::ostream& operator<<(std::ostream& os, const Point2& rhs);