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// Ford Fulkerson mit Capacity Scaling.
// Laufzeit: O(|E|^2*log(C))
struct MaxFlow { // Muss mit new erstellt werden!
static const int MAX_N = 500; // #Knoten, kein Einfluss auf die Laufzeit.
struct edge { int dest, rev; ll capacity, flow; };
vector<edge> adjlist[MAX_N];
int visited[MAX_N] = {0}, target, dfsCounter = 0;
ll capacity;
bool dfs(int x) {
if (x == target) return 1;
if (visited[x] == dfsCounter) return 0;
visited[x] = dfsCounter;
for (edge &e : adjlist[x]) {
if (e.capacity >= capacity && dfs(e.dest)) {
e.capacity -= capacity; adjlist[e.dest][e.rev].capacity += capacity;
e.flow += capacity; adjlist[e.dest][e.rev].flow -= capacity;
return 1;
}
}
return 0;
}
void addEdge(int u, int v, ll c) {
adjlist[u].push_back(edge {v, (int)adjlist[v].size(), c, 0});
adjlist[v].push_back(edge {u, (int)adjlist[u].size() - 1, 0, 0});
}
ll maxFlow(int s, int t) {
capacity = 1L << 62;
target = t;
ll flow = 0L;
while (capacity) {
while (dfsCounter++, dfs(s)) {
flow += capacity;
}
capacity /= 2;
}
return flow;
}
};
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