Add C++ util file

include/aoc.hpp

@@ -0,0 +1,107 @@
+#pragma once
+
+#include <vector>
+
+typedef long long ll;
+typedef unsigned long long ull;
+
+template <typename T> struct Coord {
+	T x, y;
+
+	Coord() : Coord(0, 0) {}
+
+	Coord(const T x, const T y) {
+		this->x = x;
+		this->y = y;
+	}
+
+	Coord<T> operator-() { return {-this->x, -this->y}; }
+
+	Coord<T> &operator+=(const Coord<T> &other) {
+		x += other.x;
+		y += other.y;
+		return *this;
+	}
+
+	Coord<T> &operator-=(const Coord<T> &other) {
+		x -= other.x;
+		y -= other.y;
+		return *this;
+	}
+
+	Coord<T> &operator*=(const T other) {
+		x *= other;
+		y *= other;
+		return *this;
+	}
+
+	Coord<T> &operator/=(const T other) {
+		x /= other;
+		y /= other;
+		return *this;
+	}
+
+	std::vector<Coord<T>> nearby(const Coord<T> &cMin, const Coord<T> &cMax) {
+		std::vector<Coord<T>> ret;
+		const T xMin = std::max(this->x - 1, cMin.x);
+		const T xMax = std::min(this->x + 1, cMax.x);
+		const T yMin = std::max(this->y - 1, cMin.y);
+		const T yMax = std::min(this->y + 1, cMax.y);
+		for (T x = xMin; x <= xMax; x++) {
+			for (T y = yMin; y <= yMax; y++) {
+				Coord<T> xy(x, y);
+				if (*this != xy) {
+					ret.push_back(xy);
+				}
+			}
+		}
+		return ret;
+	}
+
+	std::vector<Coord<T>> nearby(const Coord<T> &cMax) {
+		return this->nearby(Coord<T>(), cMax);
+	}
+};
+
+template <typename T>
+Coord<T> operator+(const Coord<T> &lhs, const Coord<T> &rhs) {
+	Coord<T> result = lhs;
+	result += rhs;
+	return result;
+}
+
+template <typename T>
+Coord<T> operator-(const Coord<T> &lhs, const Coord<T> &rhs) {
+	Coord<T> result = lhs;
+	result -= rhs;
+	return result;
+}
+
+template <typename T> Coord<T> operator*(const Coord<T> &lhs, const T rhs) {
+	Coord<T> result = lhs;
+	result *= rhs;
+	return result;
+}
+
+template <typename T> Coord<T> operator/(const Coord<T> &lhs, const T rhs) {
+	Coord<T> result = lhs;
+	result /= rhs;
+	return result;
+}
+
+template <typename T>
+inline bool operator==(const Coord<T> &lhs, const Coord<T> &rhs) {
+	return lhs.x == rhs.x && lhs.y == rhs.y;
+}
+
+template <> struct std::hash<Coord<int>> {
+	std::size_t operator()(const Coord<int> &c) const noexcept {
+		return (c.x << (sizeof(std::size_t) / 2)) - c.x + c.y;
+	}
+};
+
+template <> struct std::hash<Coord<ull>> {
+	std::size_t operator()(const Coord<ull> &c) const noexcept {
+		return (c.x << (sizeof(std::size_t) / 2)) - c.x + c.y;
+	}
+};