AdventOfCode2024/include/aoc/GuardGallivant.hpp

54 lines
2.3 KiB
C++

// Solutions to the Advent Of Code 2024.
// Copyright (C) 2024-2025 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>
#include <vector>
#include <aoc/common/Grid.hpp>
#include <aoc/common/Point2.hpp>
#include <aoc/framework/LinesSolver.hpp>
class GuardGallivant
: public LinesSolver
{
public:
virtual const std::string getPuzzleName() const override;
virtual const int getPuzzleDay() const override;
virtual void processDataLine(const std::string& line) override;
virtual void finish() override;
private:
typedef Grid<bool> VisitGrid;
typedef Grid<std::bitset<4>> PathGrid;
static constexpr size_t getStartDirectionIndex();
static constexpr char getStartChar();
static constexpr char getObstructionChar();
static constexpr char getEmptyChar();
Point2 start_{};
void tracePath();
bool tracePathCycleTest(const Point2& startPosition, const size_t startDirectionIndex, PathGrid& mainPathGrid,
PathGrid& cyclePathGrid);
bool checkTurn(const Point2& current, const Point2& next, size_t& directionIndex, PathGrid& pathGrid);
void visitPosition(const Point2& current, const size_t directionIndex, VisitGrid& visitGrid);
void tracePosition(const Point2& current, const size_t directionIndex, PathGrid& pathGrid);
void backtracePath(const Point2& current, const size_t directionIndex, PathGrid& pathGrid);
void backtraceTurn(const Point2& current, const size_t reverseTurnDirectionIndex, PathGrid& 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;
bool isObstruction(const Point2& position) const;
};