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struct PushRelabel {
vector<vector<ll>> capacitie, flow;
vector<ll> excess;
vector<int> height, seen, list;
int n;
PushRelabel(int n) {
this->n = n;
capacities.assign(n, vector<ll>(n));
flow.assign(n, vector<ll>(n));
excess.assign(n, 0);
height.assign(n, 0);
seen.assign(n, 0);
list.assign(n - 2, 0);
}
inline void addEdge(int u, int v, ll c) {capacities[u][v] += c;}
void push(int u, int v) {
ll send = min(excess[u], capacities[u][v] - flow[u][v]);
flow[u][v] += send; flow[v][u] -= send;
excess[u] -= send; excess[v] += send;
}
void relabel(int v) {
int minHeight = INT_INF;
for (int u = 0; u < n; u++) {
if (capacities[v][u] - flow[v][u] > 0) {
minHeight = min(minHeight, height[u]);
height[v] = minHeight + 1;
}}}
void discharge(int v) {
while (excess[v] > 0) {
if (seen[v] < n) {
int u = seen[v];
if (capacities[v][u] - flow[v][u] > 0 && height[v] > height[u]) {
push(v, u);
} else seen[v]++;
} else {
relabel(v);
seen[v] = 0;
}}}
void moveToFront(int v) {
int temp = list[v];
for (int u = v; u > 0; u--) list[u] = list[u - 1];
list[0] = temp;
}
ll maxFlow(int source, int target) {
for (int v = 0, p = 0; v < n; v++)
if (v != source && v != target) list[p++] = v;
height[source] = n;
excess[source] = INF;
for (int v = 0; v < n; v++) push(source, v);
int p = 0;
while (p < n - 2) {
int v = list[p], oldHeight = height[v];
discharge(v);
if (height[v] > oldHeight) {
moveToFront(p);
p = 0;
} else p++;
}
ll maxflow = 0;
for (int v = 0; v < n; v++) maxflow += flow[source][v];
return maxflow;
}
};
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