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// Ford Fulkerson with capacity scaling.
// Laufzeit: O(|E|^2 * log C)
const int MAXN = 190000, MAXC = 1<<29;
struct edge { int dest, capacity, rev; };
vector<edge> adj[MAXN];
int vis[MAXN], target, iter, cap;
void addedge(int x, int y, int c) {
adj[x].push_back(edge {y, c, (int)adj[y].size()});
adj[y].push_back(edge {x, 0, (int)adj[x].size() - 1});
}
bool dfs(int x) {
if (x == target) return 1;
if (vis[x] == iter) return 0;
vis[x] = iter;
for (edge& e: adj[x])
if (e.capacity >= cap && dfs(e.dest)) {
e.capacity -= cap;
adj[e.dest][e.rev].capacity += cap;
return 1;
}
return 0;
}
int maxflow(int S, int T) {
cap = MAXC, target = T;
int flow = 0;
while(cap) {
while(++iter, dfs(S))
flow += cap;
cap /= 2;
}
return flow;
}
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