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#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <string.h>
#define NMAX 1001
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
int n, m, FL;
int c[NMAX][NMAX], f[NMAX][NMAX], t[NMAX];
vector <int> v[NMAX];
int BF(int s, int d)
{
int nod, vec, sz, j;
queue <int> Q;
memset(t, 0, sizeof(t));
t[s]=-1;
Q.push(s);
while(!Q.empty())
{
nod = Q.front();
Q.pop();
sz = v[nod].size();
for(j=0; j<sz; ++j)
{
vec = v[nod][j];
if(t[vec] || c[nod][vec]==f[nod][vec])
continue;
t[vec] = nod;
Q.push(vec);
if(vec==d)return 1;
}
}
return 0;
}
void dinic(int s, int d)
{
int i, j, FC;
while(BF(s, d))
{
for(i=1; i<=n; ++i)
{
if(!t[i] || c[i][d]==f[i][d] || c[i][n]==0)
continue;
FC = c[i][d]-f[i][d];
for(j=i; j>s; j=t[j])
FC=min(FC, c[t[j]][j]-f[t[j]][j]);
if(!FC)
continue;
f[i][d]+=FC;
f[d][i]-=FC;
for(j=i; j>s; j=t[j])
{
f[t[j]][j]+=FC;
f[j][t[j]]-=FC;
}
FL+=FC;
}
}
}
int main()
{
int i, x, y, cap;
fin>>n>>m;
for(i=1; i<=m; ++i)
{
fin>>x>>y>>cap;
v[x].push_back(y);
v[y].push_back(x);
c[y][x]=0;
c[x][y]=cap;
}
dinic(1, n);
fout<<FL;
return 0;
}