Add solution for "Day 14: Restroom Redoubt", part 2

include/aoc/Math.hpp

@@ -15,8 +15,26 @@
 
 #pragma once
 
+#include <tuple>
+
 class Math
 {
 public:
+    /// <summary>
+    /// Calculates an integer exponentiation.
+    /// </summary>
+    /// <param name="base">Base of the exponentiation.</param>
+    /// <param name="exponent">Exponent of the exponentiation</param>
+    /// <returns>'base' raised to the power of 'exponent'.</returns>
     static int ipow(const int base, const int exponent);
+
+    /// <summary>
+    /// Calculates the greatest common divisor gcd(a, b) and the coefficients x and y of Bézout's identity
+    /// ax + by = gcd(a, b). If a and b are coprime, then x is the modular multiplicative inverse of a modulo b, and y
+    /// is the modular multiplicative inverse of b modulo a.
+    /// </summary>
+    /// <param name="a"></param>
+    /// <param name="b"></param>
+    /// <returns>A tuple of the gcd(a, b), x, and y.</returns>
+    static std::tuple<int, int, int> extendedEuclid(const int a, const int b);
 };

include/aoc/Point2.hpp

@@ -43,4 +43,5 @@ class Point2
     Point2& operator+=(const Point2& rhs);
     Point2& operator-=(const Point2& rhs);
     Point2& operator*=(const int rhs);
+    int& operator[](size_t coordinateIndex);
 };

include/aoc/RestroomRedoubt.hpp

@@ -16,14 +16,16 @@
 #pragma once
 
 #include <array>
+#include <vector>
 
+#include <aoc/Point2.hpp>
 #include <aoc/Solver.hpp>
 
 class RestroomRedoubt
     : public Solver
 {
 public:
-    RestroomRedoubt(const int width = 101, const int height = 103);
+    RestroomRedoubt(const int width = 101, const int height = 103, const bool runPart2 = true);
     virtual const std::string getPuzzleName() const override;
     virtual const int getPuzzleDay() const override;
     virtual void processDataLine(const std::string& line) override;
@@ -33,6 +35,10 @@ class RestroomRedoubt
     const int height_;
     const int halfWidth_;
     const int halfHeight_;
+    const bool runPart2_;
     std::array<int, 4> quadrants_;
+    std::vector<std::pair<Point2, Point2>> robots_;
     static constexpr int getNPredictionSeconds();
+    static constexpr int getEasterEggThreshold();
+    void findEasterEgg();
 };