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/**
* Author: Isaac
* Date:
* License:
* Description: Maximum flow (zero capacity edges are residual edges). Solves problems 10000 vertices and 1000000 edges, worst-case has very few edges.
* Time: O(V^3)
* Status:
*/
typedef long long LL;
struct Edge {
int from, to, cap, flow, index;
Edge(int from, int to, int cap, int flow, int index) :
from(from), to(to), cap(cap), flow(flow), index(index) {}
};
struct PushRelabel {
int N;
vector<vector<Edge> > G;
vector<LL> excess;
vector<int> dist, active, count;
queue<int> Q;
PushRelabel(int N) : N(N), G(N), excess(N), dist(N), active(N), count(2*N) {}
void AddEdge(int from, int to, int cap) {
G[from].push_back(Edge(from, to, cap, 0, G[to].size()));
if (from == to) G[from].back().index++;
G[to].push_back(Edge(to, from, 0, 0, G[from].size() - 1));
}
void Enqueue(int v) {
if (!active[v] && excess[v] > 0) { active[v] = true; Q.push(v); }
}
void Push(Edge &e) {
int amt = int(min(excess[e.from], LL(e.cap - e.flow)));
if (dist[e.from] <= dist[e.to] || amt == 0) return;
e.flow += amt;
G[e.to][e.index].flow -= amt;
excess[e.to] += amt;
excess[e.from] -= amt;
Enqueue(e.to);
}
void Gap(int k) {
for (int v = 0; v < N; v++) {
if (dist[v] < k) continue;
count[dist[v]]--;
dist[v] = max(dist[v], N+1);
count[dist[v]]++;
Enqueue(v);
}
}
void Relabel(int v) {
count[dist[v]]--;
dist[v] = 2*N;
for (int i = 0; i < G[v].size(); i++)
if (G[v][i].cap - G[v][i].flow > 0)
dist[v] = min(dist[v], dist[G[v][i].to] + 1);
count[dist[v]]++;
Enqueue(v);
}
void Discharge(int v) {
for (int i = 0; excess[v] > 0 && i < G[v].size(); i++) Push(G[v][i]);
if (excess[v] > 0) {
if (count[dist[v]] == 1)
Gap(dist[v]);
else
Relabel(v);
}
}
LL GetMaxFlow(int s, int t) {
count[0] = N-1;
count[N] = 1;
dist[s] = N;
active[s] = active[t] = true;
for (int i = 0; i < G[s].size(); i++) {
excess[s] += G[s][i].cap;
Push(G[s][i]);
}
while (!Q.empty()) {
int v = Q.front();
Q.pop();
active[v] = false;
Discharge(v);
}
LL totflow = 0;
for (int i = 0; i < G[s].size(); i++) totflow += G[s][i].flow;
return totflow;
}
};
int main() {
int n, m;
scanf("%d%d", &n, &m);
//FASTFLOW
PushRelabel pr(n);
for (int i = 0; i < m; i++) {
int a, b, c;
scanf("%d%d%d", &a, &b, &c);
if (a == b) continue;
pr.AddEdge(a-1, b-1, c);
pr.AddEdge(b-1, a-1, c);
}
printf("%Ld\n", pr.GetMaxFlow(0, n-1));
return 0;
}
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