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#include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#define NMAX 1000
#define MMAX 5000
#define INF 550000000
using namespace std;
bool dest, uz[NMAX + 5];
int n, m, flux;
int f[NMAX + 5][NMAX + 5], c[NMAX + 5][NMAX + 5];
int from[NMAX + 5], mincf[NMAX + 5];
vector<int> v[NMAX + 5];
void update_flux() {
int minf = INF + 5;
for(int i = n; from[i] != 0; i = from[i])
minf = min(minf, c[from[i]][i] - f[from[i]][i]);
if(!minf)
return;
flux += minf;
for(int i = n; from[i] != 0; i = from[i]) {
f[from[i]][i] += minf;
f[i][from[i]] -= minf;
}
}
int bfs(int start) {
for(int i = 1; i <= n; i++)
uz[i] = false;
queue<int> q;
q.push(start);
while(!q.empty()) {
int nod = q.front();
q.pop();
uz[nod] = true;
if(nod == n)
continue;
for(int x: v[nod]) {
if(c[nod][x] == f[nod][x] || uz[x])
continue;
from[x] = nod;
uz[x] = true;
q.push(x);
}
}
return uz[n];
}
int main() {
freopen("maxflow.in", "r", stdin);
freopen("maxflow.out", "w", stdout);
int x, y, z;
scanf("%d %d", &n, &m);
for(int i = 1; i <= m; i++) {
scanf("%d %d %d", &x, &y, &z);
c[x][y] = z;
v[x].push_back(y);
v[y].push_back(x);
}
mincf[0] = c[0][1] = INF + 5;
while(bfs(1))
for(int nod: v[n]) {
if(!uz[nod] || c[nod][n] == f[nod][n])
continue;
from[n] = nod;
update_flux();
}
printf("%d", flux);
return 0;
}