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#include <bits/stdc++.h>
//Edmonds-Karp - O(min(V*E^2, E*Fmax))
using namespace std;
ifstream f("maxflow.in");
ofstream g("maxflow.out");
const int NMAX = 1e3;
int capacitate[NMAX + 1][NMAX + 1], flux[NMAX + 1][NMAX + 1];
vector<int> G[NMAX + 1];
int vis[NMAX + 1], p[NMAX + 1];
int n, m;
int bfs(int src, int dest) {
for(int i = 1; i <= n; i++) {
vis[i] = 0;
p[i] = 0;
}
queue<int> q;
q.push(src);
vis[src] = 1;
while(!q.empty()) {
int node = q.front();
q.pop();
for(auto vecin : G[node]) {
if(!vis[vecin]) {
if(capacitate[node][vecin] - flux[node][vecin] > 0) {
q.push(vecin);
vis[vecin] = 1;
p[vecin] = node;
}
}
}
}
if(vis[dest] == 0) {
return 0;
}
vector<int> path;
int x = dest;
while(x != 0) {
path.push_back(x);
x = p[x];
}
reverse(path.begin(), path.end());
int flow = 1e9;
for(int i = 0; i < (int)path.size() - 1; i++) {
int x = path[i];
int y = path[i + 1];
flow = min(flow, capacitate[x][y] - flux[x][y]);
}
for(int i = 0; i < (int)path.size() - 1; i++) {
int x = path[i];
int y = path[i + 1];
flux[x][y] += flow;
flux[y][x] -= flow;
}
return flow;
}
int main() {
f >> n >> m;
while(m--) {
int x, y, c;
f >> x >> y >> c;
capacitate[x][y] = c;
G[x].push_back(y);
G[y].push_back(x);
}
int maxFlow = 0;
while(1) {
int flow = bfs(1, n);
if(flow == 0) {
break;
}
maxFlow += flow;
}
g << maxFlow;
return 0;
}