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#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
vector<vector<int>> la, grafRez;
vector<int> tata;
queue<int> q;
vector<bool> viz;
int BFS()
{
int n = la.size() - 1;
viz.resize(n + 1, false);
int maxFlow = 0;
q.push(1);
viz[1] = true;
while (!q.empty())
{
int nCurent = q.front();
q.pop();
for (auto vecin : la[nCurent])
{
if (!viz[vecin] && vecin != n && grafRez[nCurent][vecin] > 0)
{
viz[vecin] = true;
q.push(vecin);
tata[vecin] = nCurent;
}
}
}
for (auto adiacent : la[n])
{
if (!viz[adiacent])
continue;
int F = grafRez[adiacent][n];
int current = adiacent;
while (current != 1)
{
F = min(F, grafRez[tata[current]][current]);
current = tata[current];
}
grafRez[adiacent][n] -= F;
grafRez[n][adiacent] += F;
current = adiacent;
while (current != 1)
{
current = tata[current];
grafRez[tata[current]][current] -= F;
grafRez[current][tata[current]] += F;
}
maxFlow += F;
}
return maxFlow;
}
int getMaxFlow()
{
int n = la.size() - 1;
tata.resize(n + 1, -1);
int totalMaxFlow = 0;
int pathFlow = BFS(); //primul augmenting path
while (pathFlow)
{
totalMaxFlow += pathFlow;
pathFlow = BFS();
}
return totalMaxFlow;
}
int main()
{
int n, m;
fin >> n >> m;
la.resize(n + 1);
grafRez.resize(n + 1, vector<int>(n + 1, 0));
for (int i = 0; i < m; i++)
{
int x, y, z;
fin >> x >> y >> z;
la[x].push_back(y);
la[y].push_back(x);
grafRez[x][y] += z;
}
fout << getMaxFlow();
fin.close();
fout.close();
return 0;
}