Add solution for "Day 20: Race Condition", part 1

include/aoc/RaceCondition.hpp

@@ -0,0 +1,37 @@
+// Solutions to the Advent Of Code 2024.
+// Copyright (C) 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 <aoc/common/Grid.hpp>
+#include <aoc/framework/LinesSolver.hpp>
+
+class RaceCondition
+    : public LinesSolver<int64_t, int64_t>
+{
+public:
+    RaceCondition(const int threshold = 100);
+    virtual const std::string getPuzzleName() const override;
+    virtual const int getPuzzleDay() const override;
+    virtual void finish() override;
+private:
+    static constexpr char getStartChar();
+    static constexpr char getWallChar();
+    static constexpr int getCheatLength();
+    const std::array<Point2, 8> doubleSteps_{ Point2::down * 2, Point2::downRight, Point2::right * 2,
+        Point2::upRight, Point2::up * 2, Point2::upLeft, Point2::left * 2, Point2::downLeft };
+    int threshold_;
+    void checkCheat(const Point2& position, Grid<int>& times);
+};