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#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#include <cstring>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
const int Nmax = 1005;
const int oo = (1<<30);
vector <int> G[Nmax];
int N,M,destFlow;
int maxFlow[Nmax][Nmax],currentFlow[Nmax][Nmax],Use[Nmax],TT[Nmax];
int BFS()
{
memset(Use,0,sizeof(Use));
queue <int> Q;
Q.push(1);
Use[1]=1;
while(!Q.empty())
{
int Nod=Q.front();
Q.pop();
if(Nod==N)
continue;
for(int i=0;i<G[Nod].size();i++)
{
int Vecin=G[Nod][i];
if(maxFlow[Nod][Vecin] == currentFlow[Nod][Vecin] || Use[Vecin] )
continue;
Use[Vecin]=1;
TT[Vecin]=Nod;
Q.push(Vecin);
}
}
return Use[N];
}
void read()
{
fin>>N>>M;
for(int i=1;i<=M;i++)
{
int x,y,f;
fin>>x>>y>>f;
maxFlow[x][y]+=f;
G[x].push_back(y);
G[y].push_back(x);
}
}
int main()
{
read();
for( destFlow = 0; BFS() ; )
{
for(int i=0;i<G[N].size();i++)
{
int Nod=G[N][i];
if(maxFlow[Nod][N]==currentFlow[Nod][N] || !Use[Nod])
continue;
TT[N]=Nod;
int maxAddFlow=oo;
for(int nod = Nod ; nod != 1 ; nod = TT[nod])
maxAddFlow=min(maxAddFlow,maxFlow[TT[nod]][nod]-currentFlow[TT[nod]][nod]);
if(maxAddFlow == 0)
continue;
for(int nod = Nod ; nod >0 ; nod = TT[nod])
{
currentFlow[TT[nod]][nod]+=maxAddFlow;
currentFlow[nod][TT[nod]]-=maxAddFlow;
}
destFlow+=maxAddFlow;
}
}
fout<<destFlow<<"\n";
return 0;
}