Add solution for "Day 13: Claw Contraption", part 1

include/aoc/ClawContraption.hpp

@@ -0,0 +1,35 @@
+// 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/Solver.hpp>
+#include <aoc/Point2.hpp>
+
+class ClawContraption : public Solver
+{
+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:
+    Point2 buttonA_;
+    Point2 buttonB_;
+    static constexpr int getNMaxButtonPushes();
+    static constexpr int getButtonACost();
+    static constexpr int getButtonBCost();
+    long long int calcTokenCost(const Point2& buttonA, const Point2& buttonB, const Point2& prize);
+};

src/ClawContraption.cpp

@@ -0,0 +1,102 @@
+// 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/>.
+
+#include <aoc/ClawContraption.hpp>
+
+#include <sstream>
+
+const std::string ClawContraption::getPuzzleName() const
+{
+    return "Claw Contraption";
+}
+
+const int ClawContraption::getPuzzleDay() const
+{
+    return 13;
+}
+
+void ClawContraption::processDataLine(const std::string& line)
+{
+    if (!line.empty())
+    {
+        std::istringstream stream{ line };
+        std::string token;
+        char c;
+        int x;
+        int y;
+
+        stream >> token;
+        if (token == "Button")
+        {
+            stream >> c;
+            std::getline(stream, token, '+');
+            stream >> x;
+            std::getline(stream, token, '+');
+            stream >> y;
+            if (c == 'A')
+            {
+                buttonA_ = { x, y };
+            }
+            else
+            {
+                buttonB_ = { x, y };
+            }
+        }
+        else
+        {
+            std::getline(stream, token, '=');
+            stream >> x;
+            std::getline(stream, token, '=');
+            stream >> y;
+            part1 += calcTokenCost(buttonA_, buttonB_, { x, y });
+        }
+    }
+}
+
+void ClawContraption::finish()
+{
+}
+
+constexpr int ClawContraption::getNMaxButtonPushes()
+{
+    return 100;
+}
+
+constexpr int ClawContraption::getButtonACost()
+{
+    return 3;
+}
+
+constexpr int ClawContraption::getButtonBCost()
+{
+    return 1;
+}
+
+long long int ClawContraption::calcTokenCost(const Point2& buttonA, const Point2& buttonB, const Point2& prize)
+{
+    long long int p{ prize.y * buttonB.x - prize.x * buttonB.y };
+    long long int q{ buttonA.y * buttonB.x - buttonA.x * buttonB.y };
+    long long int a{ p / q };
+    if (a * q != p || a > getNMaxButtonPushes())
+    {
+        return 0;
+    }
+    long long int b{ (prize.x - a * buttonA.x) / buttonB.x };
+    if (b > getNMaxButtonPushes())
+    {
+        return 0;
+    }
+    return a * getButtonACost() + b * getButtonBCost();
+}

src/Program.cpp

@@ -33,6 +33,7 @@
 #include <aoc/HoofIt.hpp>
 #include <aoc/PlutonianPebbles.hpp>
 #include <aoc/GardenGroups.hpp>
+#include <aoc/ClawContraption.hpp>
 #include <aoc/LanParty.hpp>
 
 void Program::run()
@@ -63,6 +64,7 @@ void Program::runSolvers()
     runSolver<HoofIt>(solverEngine);
     runSolver<PlutonianPebbles>(solverEngine);
     runSolver<GardenGroups>(solverEngine);
+    runSolver<ClawContraption>(solverEngine);
     runSolver<LanParty>(solverEngine);
 }
 

tests/src/TestCases.cpp

@@ -30,6 +30,7 @@
 #include <aoc/HoofIt.hpp>
 #include <aoc/PlutonianPebbles.hpp>
 #include <aoc/GardenGroups.hpp>
+#include <aoc/ClawContraption.hpp>
 #include <aoc/LanParty.hpp>
 
 #define REQUIRE_MESSAGE(cond, msg) if (!(cond)) { INFO(msg); REQUIRE(cond); }
@@ -206,6 +207,19 @@ TEST_CASE("[GardenGroupsTests]")
     }
 }
 
+TEST_CASE("[ClawContraptionTests]")
+{
+    TestContext test;
+    SECTION("FullData")
+    {
+        test.run(std::make_unique<ClawContraption>(), 36571, 0, test.getInputPaths());
+    }
+    SECTION("ExampleData")
+    {
+        test.run(std::make_unique<ClawContraption>(), 480, 0, test.getExampleInputPaths());
+    }
+}
+
 TEST_CASE("[LanPartyTests]")
 {
     TestContext test;