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///Flux maxim (infoarena)
#include <fstream>
#include <algorithm>
#include <queue>
#include <cmath>
using namespace std;
ifstream cin("maxflow.in");
fstream cout("maxflow.out");
const int N=1e3;
const int INF=2e9;
vector<int>v[N+1];
int flux[N+1][N+1];
int t[N+1];
bool viz[N+1];
int n;
bool bfs(int p)
{
for(int i=1;i<=n;i++)
viz[i]=false;
queue<int>q;
q.push(p);
viz[p]=true;
while(!q.empty())
{
int p=q.front();
q.pop();
if(p==n)
return true;
for(auto i:v[p])
{
if(!viz[i] && flux[p][i]>0)
{
q.push(i);
t[i]=p;
viz[i]=true;
}
}
}
return false;
}
int main()
{
int m, i, j, mini=INF, x, y, c;
long long maxi=0;
cin >> n >> m;
for(i=1;i<=m;i++)
{
cin >> x >> y >> c;
flux[x][y]=c;
v[x].push_back(y);
v[y].push_back(x);
}
while(bfs(1))
{
for(auto i:v[n])
{
if(!viz[i] || flux[i][n]<=0)
continue;
mini=INF;
t[n]=i;
x=n;
while(x!=1)
{
mini=min(mini,flux[t[x]][x]);
x=t[x];
}
if(mini==0)
continue;
maxi+= mini;
x=n;
while(x!=1)
{
flux[x][t[x]]=flux[x][t[x]]+mini;
flux[t[x]][x]=flux[t[x]][x]-mini;
x=t[x];
}
}
}
cout<<maxi;
return 0;
}