zmodn

test (2735B)

---

 #if 0
 
 cc=${CC:-g++}
 bin="$(mktemp)"
 ${cc} -x c++ -std=c++20 -o "$bin" "$(realpath $0)"
 "$bin"
 
 exit 0
 #endif
 
 #include "zmodn.h"
 #include <concepts>
 #include <functional>
 #include <iostream>
 #include <optional>
 
 template<typename S, typename T>
 requires std::convertible_to<S, T> || std::convertible_to<T, S>
 void assert_equal(S actual, T expected) {
 	if (actual != expected) {
 		std::cout << "Error!" << std::endl;
 		std::cout << "Expected: " << expected << std::endl;
 		std::cout << "But got:  " << actual << std::endl;
 		exit(1);
 	}
 }
 
 class Test {
 public:
 	std::string name;
 	std::function<void()> f;
 } tests[] = {
 {
 	.name = "Constructor 2 mod 3",
 	.f = []() {
 		Zmod<3> two = Zmod<3>(2);
 		assert_equal(two.toint(), INT64_C(2));
 	}
 },
 {
 	.name = "Constructor -7 mod 3",
 	.f = []() {
 		Zmod<3> z = -7;
 		assert_equal(z, Zmod<3>(2));
 	}
 },
 {
 	.name = "1+1 mod 2",
 	.f = []() {
 		auto oneplusone = Zmod<2>(1) + Zmod<2>(1);
 		assert_equal(oneplusone, Zmod<2>(0));
 	}
 },
 {
 	.name = "2 -= 5 (mod 4)",
 	.f = []() {
 		Zmod<4> z = 2;
 		auto diff = (z -= 5);
 		assert_equal(z, Zmod<4>(1));
 		assert_equal(diff, Zmod<4>(1));
 	}
 },
 {
 	.name = "Inverse of 0 mod 2",
 	.f = []() {
 		Zmod<2> z = 0;
 		auto inv = z.inverse();
 		assert_equal(inv.has_value(), false);
 	}
 },
 {
 	.name = "Inverse of 1 mod 2",
 	.f = []() {
 		Zmod<2> z = 1;
 		auto inv = z.inverse();
 		assert_equal(inv.has_value(), true);
 		assert_equal(inv.value(), Zmod<2>(1));
 	}
 },
 {
 	.name = "Inverse of 5 mod 7",
 	.f = []() {
 		Zmod<7> z = 5;
 		auto inv = z.inverse();
 		assert_equal(inv.has_value(), true);
 		assert_equal(inv.value(), Zmod<7>(3));
 	}
 },
 {
 	.name = "Inverse of 4 mod 12",
 	.f = []() {
 		Zmod<12> z = 4;
 		auto inv = z.inverse();
 		assert_equal(inv.has_value(), false);
 	}
 },
 {
 	.name = "4 / 7 (mod 12)",
 	.f = []() {
 		Zmod<12> n = 4;
 		Zmod<12> d = 7;
 		auto inv = n / d;
 		assert_equal(inv.has_value(), true);
 		assert_equal(inv.value(), Zmod<12>(4));
 	}
 },
 {
 	.name = "4 /= 7 (mod 12)",
 	.f = []() {
 		Zmod<12> n = 4;
 		Zmod<12> d = 7;
 		auto inv = (n /= d);
 		assert_equal(inv.has_value(), true);
 		assert_equal(inv.value(), Zmod<12>(4));
 		assert_equal(n, Zmod<12>(4));
 	}
 },
 {
 	.name = "Multiplication overflow",
 	.f = []() {
 		Zmod<10> n = 8;
 		Zmod<10> m = 9;
 		auto prod = m * n;
 		assert_equal(prod.toint(), 2);
 	}
 },
 {
 	.name = "Multiplication and assignment overflow",
 	.f = []() {
 		Zmod<10> n = 8;
 		Zmod<10> m = 9;
 		n *= m;
 		assert_equal(n.toint(), 2);
 	}
 },
 {
 	.name = "2^12 mod 154",
 	.f = []() {
 		Zmod<154> b = 2;
 		auto p = b ^ 12;
 		assert_equal(p, 92);
 	}
 },
 };
 
 int main() {
 	for (auto t : tests) {
 		std::cout << t.name << ": ";
 		t.f();
 		std::cout << "OK" << std::endl;
 	}
 	std::cout << "All tests passed" << std::endl;
 	return 0;
 }