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#include <fstream>
#include <vector>
using namespace std;
ifstream cin("maxflow.in");
ofstream cout("maxflow.out");
int n,m,ok,cap[1005],tt[1005],c[1005][1005];
long long s,fmax[1005];
vector <int> v[1005];
void bfs(int x)
{
fmax[x]=0;
if(c[x][n])
{
fmax[x]=min(cap[x],c[x][n]);
}
for(int i=0; i<v[x].size()&&fmax[x]<cap[x]; i++)
{
int y=v[x][i];
if(c[x][y]&&cap[y]==0&&y!=n)
{
cap[y]=min(cap[x],c[x][y]);
tt[y]=x;
bfs(y);
fmax[x]+=fmax[y];
fmax[x]=min(fmax[x],1LL*cap[x]);
}
}
}
void bfs2(int x, int flow)
{
if(flow==0) return;
if(c[x][n])
{
int aux;
aux=min(c[x][n],flow);
c[x][n]-=aux;
c[n][x]+=aux;
fmax[x]-=aux;
flow-=aux;
}
long long sum=0;
for(int i=0; i<v[x].size()&&fmax[x]&&flow; i++)
{
int y=v[x][i];
if(tt[y]==x)
{
int aux=min(fmax[y],1LL*flow);
c[x][y]-=aux;
c[y][x]+=aux;
fmax[x]-=aux;
flow-=aux;
bfs2(y,aux);
}
}
}
int main()
{
cin>>n>>m;
for(int i=1; i<=m; i++)
{
int x,y;
cin>>x>>y;
cin>>c[x][y];
v[x].push_back(y);
v[y].push_back(x);
}
do{
ok=0;
cap[1]=1000000005;
bfs(1);
for(int i=2; i<n; i++)
{
if(cap[i]>0&&c[i][n]) ok=1;
}
s+=fmax[1];
bfs2(1,fmax[1]);
for(int i=1; i<=n; i++)
{
cap[i]=0;
tt[i]=0;
fmax[i]=0;
}
}while(ok);
cout<<s<<'\n';
return 0;
}