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#include<cstdio>
#include<vector>
#include<queue>
using namespace std;
vector<int> con[1010];
int n,m,x,y,z,res;
int cap[1010][1010],flux[1010][1010],tata[1010];
bool viz[1010];
queue<int> q;
int bfs()
{
for(int i=1;i<=1000;i++)
{
viz[i]=0;
}
viz[1]=1;
q.push(1);
int curr,next;
while(!q.empty())
{
curr=q.front();
if(curr!=n)
{
for(vector<int>::iterator it=con[curr].begin();it!=con[curr].end();it++)
{
next=*it;
if(flux[curr][next]<cap[curr][next]&&viz[next]==0)
{
viz[next]=1;
q.push(next);
tata[next]=curr;
}
}
}
q.pop();
}
return viz[n];
}
int main()
{
freopen("maxflow.in","r",stdin);
freopen("maxflow.out","w",stdout);
scanf("%d %d",&n,&m);
for(int i=1;i<=m;i++)
{
scanf("%d %d %d",&x,&y,&z);
con[x].push_back(y);
cap[x][y]+=z;
}
while(bfs())
{
for(vector<int>::iterator it=con[n].begin();it!=con[n].end();it++)
{
int curr=*it;
if(flux[curr][n]<cap[curr][n]&&viz[curr]==1)
{
int minfl=cap[curr][n]-flux[curr][n];
while(tata[curr]!=0)
{
if(cap[tata[curr]][curr]-flux[tata[curr]][curr]<minfl)
{
minfl=cap[tata[curr]][curr]-flux[tata[curr]][curr];
}
curr=tata[curr];
}
res+=minfl;
curr=*it;
flux[curr][n]+=minfl;
flux[n][curr]-=minfl;
while(tata[curr]!=0)
{
flux[tata[curr]][curr]+=minfl;
flux[curr][tata[curr]]-=minfl;
curr=tata[curr];
}
}
}
}
printf("%d",res);
}