mzuenni tests

1 files changed, 46 insertions, 0 deletions

diff --git a/test/math/inversionsMerge.cpp b/test/math/inversionsMerge.cpp
new file mode 100644
index 0000000..85ab0d2
--- /dev/null
+++ b/test/math/inversionsMerge.cpp
@@ -0,0 +1,46 @@
+#include "../util.h"
+#include <math/inversionsMerge.cpp>
+
+ll naive(const vector<ll>& v) {
+	ll res = 0;
+	for (ll i = 0; i < sz(v); i++) {
+		for (ll j = 0; j < i; j++) {
+			if (v[j] > v[i]) res++;
+		}
+	}
+	return res;
+}
+
+void stress_test() {
+	ll queries = 0;
+	for (ll i = 0; i < 100'000; i++) {
+		int n = Random::integer<int>(1, 100);
+		vector<ll> v(n);
+		for (ll j = 0; j < n; j++) v[j] = (j-10) * 100000 + Random::integer<ll>(0, 10000);//values must be unique ):
+		shuffle(all(v), Random::rng);
+		ll expected = naive(v);
+		ll got = mergeSort(v);
+		if (got != expected) {
+			cerr << "got: " << got << ", expected: " << expected << FAIL;
+		}
+		queries += n;
+	}
+	cerr << "tested queries: " << queries << endl;
+}
+
+constexpr int N = 2'000'000; //10 times faster
+void performance_test() {
+	timer t;
+	auto v = Random::integers<ll>(N, -10'000, 10'000);
+	t.start();
+	hash_t hash = mergeSort(v);
+	t.stop();
+	if (t.time > 500) cerr << "too slow: " << t.time << FAIL;
+	cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl;
+}
+
+int main() {
+	stress_test();
+	performance_test();
+}
+