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#include <iostream>
#include <bits/stdc++.h>
#define MAX 1001
using namespace std;
ifstream in("maxflow.in");
ofstream out("maxflow.out");
int N,M,S,F; // Nr noduri, start, finish
vector<int> Graph[MAX];
int capacitate[MAX][MAX];
int flow[MAX][MAX];
int muchii[MAX][MAX];
int tata[MAX];
int bfs()
{
for(int i=1; i<=N; i++)
tata[i]=0;
queue<int> que;
que.push(S);
tata[S]=S;
while(!que.empty())
{
int cur = que.front();
que.pop();
for(auto next : Graph[cur])
{
if(!tata[next] && (capacitate[cur][next]-flow[cur][next]>0)) // Daca nu e deja vizitat si mai putem creste fluxul
{
tata[next] = cur;
if(next!=F)
que.push(next);
}
}
}
if(tata[F])
return 1;
return 0;
}
int Karp()
{
int maxflow =0;
while(bfs())
{
for(auto vecin : Graph[F])
if(tata[vecin] && capacitate[vecin][F]-flow[vecin][F] >0)
{
int currentFlow = 2e9;
tata[F] = vecin;
int current = F;
int previous;
while(current!=S)
{
previous = tata[current];
currentFlow = min(currentFlow, capacitate[previous][current]-flow[previous][current]);
current = previous;
}
current=F;
if(currentFlow>0)
while(current!=S) //Updatam capacitatile
{
previous = tata[current];
flow[previous][current]+=currentFlow;
flow[current][previous]-=currentFlow;
current = previous;
}
maxflow+=currentFlow;
}
}
return maxflow;
}
int main()
{
int x,y,z;
in>>N>>M;
S=1;
F=N;
for(int i=1; i<=M; i++)
{
in>>x>>y>>z;
Graph[x].push_back(y);
Graph[y].push_back(x);
capacitate[x][y]=z;
muchii[x][y]=muchii[y][x]=i;
}
out<<Karp();
return 0;
}