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#include <bits/stdc++.h>
using namespace std;
ifstream in("maxflow.in");
ofstream out("maxflow.out");
using T=int;
struct Dinic
{
struct Edge
{
int a,b,ult;
T flow,cap;
};
vector <Edge> es;
vector <int> last,dist,coada;
Dinic(int n)
{
last.assign(n+1,-1);
}
void AddEdge(int a,int b,T c)
{
es.push_back({a,b,last[a],0,c});
last[a]=es.size()-1;
es.push_back({b,a,last[b],0,0});
last[b]=es.size()-1;
}
bool bfs(int s,int t)
{
coada.clear();
dist.assign(last.size(),-1);
dist[s]=0;
coada.push_back(s);
for(int i=0; i<(int)coada.size(); i++)
{
int it=coada[i];
for(int x=last[it]; x!=-1; x=es[x].ult)
{
if(dist[es[x].b]==-1&&es[x].cap>es[x].flow)
{
dist[es[x].b]=dist[it]+1;
coada.push_back(es[x].b);
}
}
}
//for(int i=1;i<last.size();i++)
//cout<<dist[i]<<" ";
//cout<<'\n';
return (dist[t]!=-1);
}
T dfs(int s,int t,T pas)
{
T tot=0;
if(s==t||pas==0)
return pas;
for(int x=last[s]; x!=-1; x=es[x].ult)
{
if(dist[es[x].b]==dist[s]+1&&es[x].cap>es[x].flow)
{
T cat=dfs(es[x].b,t,min(pas,es[x].cap-es[x].flow));
if(cat)
{
es[x].flow+=cat;
es[x^1].flow-=cat;
tot+=cat;
pas-=cat;
}
}
if(!pas)
break;
}
return tot;
}
T Compute(int s,int t)
{
T rez=0;
while(bfs(s,t))
rez+=dfs(s,t,numeric_limits<T>::max());
return rez;
}
};
int main()
{
int n,m,i,a,b,c;
in>>n>>m;
Dinic d(n);
for(i=1; i<=m; i++)
{
in>>a>>b>>c;
d.AddEdge(a,b,c);
}
out<<d.Compute(1,n);
return 0;
}