mzuenni tests

1 files changed, 83 insertions, 0 deletions

diff --git a/test/geometry/sortAround.cpp b/test/geometry/sortAround.cpp
new file mode 100644
index 0000000..a27edc8
--- /dev/null
+++ b/test/geometry/sortAround.cpp
@@ -0,0 +1,83 @@
+#include "../util.h"
+constexpr ll EPS = 0;
+#define double ll
+#define polar polar<ll>
+#include <geometry/formulas.cpp>
+#undef polar
+#undef double
+#include <geometry/sortAround.cpp>
+
+//expected order:
+//1 8 7
+//2 . 6
+//3 4 5
+void test_tiny() {
+	vector<pt> expected = {
+		{-1, 1},
+		{-1, 0},
+		{-1,-1},
+		{ 0,-1},
+		{ 1,-1},
+		{ 1, 0},
+		{ 1, 1},
+		{ 0, 1},
+	};
+	auto got = expected;
+	for (int i = 0; i < 100'000; i++) {
+		shuffle(all(got), Random::rng);
+		sortAround(0, got);
+		if (got != expected) cerr << "error" << FAIL;
+	}
+	cerr << "tested tiny" << endl;
+}
+
+void stress_test(ll range) {
+	ll queries = 0;
+	for (int tries = 0; tries < 100'000; tries++) {
+		int n = Random::integer<int>(2, 100);
+		auto ps = Random::points<ll>(n, -range, range);
+
+		auto contains = [&](pt p){
+			for (pt pp : ps) if (pp == p) return true;
+			return false;
+		};
+
+		pt c;
+		do {
+			c = Random::point<ll>(-range, range);
+		} while (contains(c));
+
+		sortAround(c, ps);
+
+		auto isLeft = [&](pt p){return real(p - c) < 0 || (real(p - c) == 0 && imag(p - c) < 0);};
+		auto isCCW = [&](pt a, pt b){return cross(c, a, b) > 0;};
+		if (!is_partitioned(all(ps), isLeft)) cerr << "error 1" << FAIL;
+		auto mid = partition_point(all(ps), isLeft);
+		if (!is_sorted(ps.begin(), mid, isCCW)) cerr << "error 2" << FAIL;
+		if (!is_sorted(mid, ps.end(), isCCW)) cerr << "error 3" << FAIL;
+		queries += n;
+	}
+	cerr << "tested random queries: " << queries << endl;
+}
+
+constexpr int N = 2'000'000;
+void performance_test() {
+	timer t;
+	auto ps = Random::points<ll>(N, -1'000'000'000, 1'000'000'000);
+
+	t.start();
+	sortAround(0, ps);
+	t.stop();
+
+	hash_t hash = 0;
+	for (pt p : ps) hash += real(p) * imag(p);
+	if (t.time > 500) cerr << "too slow: " << t.time << FAIL;
+	cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl;
+}
+
+int main() {
+	test_tiny();
+	stress_test(100);
+	stress_test(1'000'000'000);
+	performance_test();
+}