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#include<fstream>
#include<vector>
#include<queue>
#include<cstring>
#define NMAX 1005
using namespace std;
vector<int> G[NMAX];
queue<int> q;
int n, m, x, y, z;
bool u[NMAX];
int nod, minim, flux;
int C[NMAX][NMAX];
int F[NMAX][NMAX];
int T[NMAX];
ifstream cin("maxflow.in");
ofstream cout("maxflow.out");
void reinit()
{
memset(u, 0, sizeof(u));
}
bool bfs()
{
reinit();
q.push(1);
u[1] = 1;
while(!q.empty())
{
nod = q.front();
q.pop();
for(int i = 0; i < G[nod].size(); i++)
{
int fiu = G[nod][i];
if(u[fiu] == 0 && C[nod][fiu] - F[nod][fiu] > 0)
{
q.push(fiu);
u[fiu] = 1;
T[fiu] = nod;
}
}
}
return u[n] == 1;
}
void flow_update(int tata, int fiu, int minim)
{
F[tata][fiu] += minim;
F[fiu][tata] -= minim;
}
void flux_maxim()
{
while(bfs())
{
for(int i = 0; i < G[n].size(); i++)
{
int fiu = G[n][i];
if(u[fiu] == 1)
{
minim = C[fiu][n] - F[fiu][n];
for(; T[fiu] != 0 && minim != 0; fiu = T[fiu])
{
minim = min(C[T[fiu]][fiu] - F[T[fiu]][fiu], minim);
}
}
if(minim != 0)
{
flux += minim;
fiu = G[n][i];
flow_update(fiu, n, minim);
for(; T[fiu] != 0; fiu = T[fiu])
{
flow_update(T[fiu], fiu, minim);
}
}
}
}
}
int main()
{
cin >> n >> m;
for(int i = 1; i <= m; i++)
{
cin >> x >> y >> z;
G[x].push_back(y);
C[x][y] = z;
G[y].push_back(x);
}
flux_maxim();
cout << flux;
return 0;
}