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int s, t, f; //source, target, single flow
int res[MAX_V][MAX_V]; //adj-matrix
vector< vector<int> > adjList;
int p[MAX_V]; //bfs spanning tree
void augment(int v, int minEdge) {
if (v == s) { f = minEdge; return; }
else if (p[v] != -1) {
augment(p[v], min(minEdge, res[p[v]][v]));
res[p[v]][v] -= f; res[v][p[v]] += f;
}}
nt maxFlow() { //first inititalize res, adjList, s and t
int mf = 0;
while (true) {
f = 0;
bitset<MAX_V> vis; vis[s] = true;
queue<int> q; q.push(s);
memset(p, -1, sizeof(p));
while (!q.empty()) { //BFS
int u = q.front(); q.pop();
if (u == t) break;
for (int j = 0; j < (int)adjList[u].size(); j++) {
int v = adjList[u][j];
if (res[u][v] > 0 && !vis[v]) {
vis[v] = true; q.push(v); p[v] = u;
}}}
augment(t, INF); //add found path to max flow
if (f == 0) break;
mf += f;
}
return maxFlow;
}
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