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#include <iostream>
#include <fstream>
#include <cstring>
#include <vector>
using namespace std;
const int inf = 1 << 30;
const int Nmax = 1005;
int N, M;
int C[Nmax][Nmax];
int F[Nmax][Nmax];
vector <int> G[Nmax];
int vis[Nmax];
int coada[Nmax];
int tata[Nmax];
inline bool BFS( int S, int D )
{
for ( int i = 0; i <= N; ++i )
vis[i] = 0;
int st = 1, dr = 1;
coada[1] = S;
vis[S] = 1;
tata[S] = 0;
while ( st <= dr )
{
int nod = coada[ st++ ];
for ( auto vecin: G[nod] )
{
if ( !vis[vecin] && C[nod][vecin] > F[nod][vecin] )
{
vis[vecin] = 1;
tata[vecin] = nod;
coada[ ++dr ] = vecin;
if ( vecin == D )
return true;
}
}
}
return false;
}
int EdmondsKarp( int S, int D )
{
int flow = 0, fmin;
while ( BFS( S, D ) )
{
for ( auto vecin: G[D] )
{
if ( !vis[vecin] || F[vecin][D] >= C[vecin][D] ) continue;
tata[D] = vecin;
fmin = inf;
for ( int nod = D; nod != S; nod = tata[nod] )
fmin = min( fmin, C[ tata[nod] ][nod] - F[ tata[nod] ][nod] );
if ( fmin == 0 ) continue;
for ( int nod = D; nod != S; nod = tata[nod] )
{
F[ tata[nod] ][nod] += fmin;
F[nod][ tata[nod] ] -= fmin;
}
flow += fmin;
}
}
return flow;
}
int main()
{
ifstream f("maxflow.in");
ofstream g("maxflow.out");
f >> N >> M;
for ( int i = 1, a, b, c; i <= M; ++i )
{
f >> a >> b >> c;
G[a].push_back( b );
G[b].push_back( a );
C[a][b] = c;
}
g << EdmondsKarp( 1, N );
return 0;
}