1 files changed, 81 insertions, 0 deletions
diff --git a/test/graph/stoerWagner.cpp b/test/graph/stoerWagner.cpp
new file mode 100644
index 0000000..2003f09
--- /dev/null
+++ b/test/graph/stoerWagner.cpp
@@ -0,0 +1,81 @@
+#include "../util.h"
+constexpr ll INF = LL::INF;
+
+namespace stoerWagner {
+#include <graph/stoerWagner.cpp>
+	void addEdge(int u, int v, ll c) {
+		adj[u].push_back({u, v, c});
+		adj[v].push_back({v, u, c});
+	}
+}
+
+namespace pushRelabel {
+#include <graph/pushRelabel.cpp>
+	ll minCut() {
+		ll res = INF;
+		for (int i = 0; i < sz(adj); i++) {
+			for (int j = 0; j < i; j++) {
+				if (i == j) continue;
+				res = min(res, maxFlow(i, j));
+				for (auto& v : adj) {
+					for (auto& e : v) {
+						e.f = 0;
+					}
+				}
+			}
+		}
+		return res;
+	}
+}
+
+void stress_test() {
+	ll queries = 0;
+	for (int tries = 0; tries < 5'000; tries++) {
+		int n = Random::integer<int>(2, 30);
+		int m = Random::integer<int>(n-1, max<int>(n, min<int>(500, n*(n-1) / 2 + 1)));
+
+		stoerWagner::adj.assign(n, {});
+		pushRelabel::adj.assign(n, {});
+
+		Graph<NoData> g(n);
+		g.erdosRenyi(m);
+		g.forEdges([](int a, int b){
+			ll w = Random::integer<ll>(1, 1'000'000'000'000ll);
+			stoerWagner::addEdge(a, b, w);
+			pushRelabel::addEdge(a, b, w);
+			pushRelabel::addEdge(b, a, w);
+		});
+
+		ll got = stoerWagner::stoer_wagner();
+		ll expected = pushRelabel::minCut();
+		
+		if (got != expected) cerr << "got: " << got << ", expected: " << expected << FAIL;
+		queries += n;
+	}
+	cerr << "tested random queries: " << queries << endl;
+}
+
+constexpr int N = 200;
+constexpr int M = 10000;
+void performance_test() {
+	using namespace stoerWagner;
+	timer t;
+	Graph<NoData> g(N);
+	g.erdosRenyi(M);
+	adj.assign(N, {});
+	g.forEdges([](int a, int b){
+		ll w = Random::integer<ll>(1, 1'000'000'000'000ll);
+		addEdge(a, b, w);
+	});
+
+	t.start();
+	hash_t hash = stoer_wagner();
+	t.stop();
+	if (t.time > 2000) cerr << "too slow: " << t.time << FAIL;
+	cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl;
+}
+
+int main() {
+	stress_test();
+	performance_test();
+}