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#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();
}
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