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#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
std::ifstream in("maxflow.in");
std::ofstream out("maxflow.out");
const int N=1000;
std::vector<int> v[N+1];
int n, m;
/// reziduu pe muchia i->j (capacitate-flux)
int c[N+1][N+1];
int parent[N+1];
int flux;
/// creeaza drum de la 1 la n pe muchii cu reziduu pozitiv
bool bfs()
{
std::queue<std::pair<int, int>> q;
for(int i=1; i<=n; i++) parent[i]=-1;
q.push({1, 3e5});
while(!q.empty())
{
int curr=q.front().first;
int flow_curr=q.front().second;
for(int j : v[curr])
{
if(j==n)
{
flux=flow_curr;
parent[n]=curr;
return true;
}
if(parent[j]==-1 && c[curr][j])
{
parent[j]=curr;
q.push({j, std::min(flow_curr, c[curr][j])});
}
}
q.pop();
}
return false;
}
int main()
{
int x, y, z;
int ans=0;
in>>n>>m;
for(int i=1; i<=m; i++)
{
in>>x>>y>>z;
v[x].push_back(y);
v[y].push_back(x);
c[x][y]=z;
}
while(bfs())
{
ans+=flux;
int backt=n;
while(parent[backt]!=-1)
{
c[parent[backt]][backt]-=flux;
c[backt][parent[backt]]+=flux;
backt=parent[backt];
}
}
out<<ans;
}