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#include <fstream>
#include <iostream>
#include <vector>
#include <queue>
#define INF 0x3f3f3f3f
using namespace std;
ifstream is("maxflow.in");
ofstream os("maxflow.out");
using VI = vector<int>;
using VVI = vector<VI>;
using VP = vector<pair<int, int>>;
using VVP = vector<VP>;
using VPP = vector<pair<int, pair<int, int>>>;
int n, m, answ, flow;
VI t;
VVI g, c;
queue<int> q;
void Read();
bool Flow();
int main()
{
Read();
while ( Flow() )
for ( const auto &nod : g[n] )
{
if ( nod != 1 && ( !t[nod] || c[nod][n] <= 0 ) )
continue;
t[n] = nod;
flow = INF;
for ( int x = n; t[x]; x = t[x] )
flow = min(flow, c[t[x]][x]);
if ( flow == INF )
continue;
for ( int x = n; t[x]; x = t[x] )
{
c[t[x]][x] -= flow;
c[x][t[x]] += flow;
}
answ += flow;
}
os << answ;
is.close();
os.close();
return 0;
}
bool Flow()
{
t = VI(n + 1, 0);
q.push(1);
int nod;
while ( q.size() )
{
nod = q.front();
q.pop();
if ( nod == n )
continue;
for ( const auto &nodv : g[nod] )
{
if ( nodv != 1 && !t[nodv] && c[nod][nodv] > 0 )
{
t[nodv] = nod;
q.push(nodv);
}
}
}
if ( t[n] )
return true;
return false;
}
void Read()
{
is >> n >> m;
g = VVI(n + 1);
c = VVI(n + 1, VI(n + 1));
int x, y;
for ( int i = 1; i <= m; ++i )
{
is >> x >> y;
g[x].push_back(y);
g[y].push_back(x);
is >> c[x][y];
}
}