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#include <iostream>
#include <vector>
#include <queue>
#include <algorithm>
#include <fstream>
using namespace std;
#define ff first
#define ss second
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
int mp[1115][1115], parent[1100];
bool viz[1100];
int n, m;
queue<pair<int, int>>edges;
bool bfs(int source, int sink)
{
for (int i = 1; i <= n; i++)viz[i] = 0, parent[i] = 0;
bool reached = 0;
queue<int>q;
q.push(source);
viz[source] = 1;
parent[source] = source;
while (!q.empty())
{
int crt = q.front();
q.pop();
viz[crt] = 1;
for (int i = 1; i <= n; i++)
{
if ( viz[i])continue;
if (mp[crt][i] > 0)
{
if (i == sink)
{
reached = 1;
edges.push({ crt,i });
continue;
}
q.push(i);
parent[i] = crt;
viz[i] = 1;
}
}
}
return reached;
}
int edmondsKarp(int source, int sink)
{
int rez = 0;
while (bfs(source, sink))
{
while (!edges.empty())
{
int a = edges.front().ff, b = edges.front().ss;
int Min = 10000000;
Min = min(Min, mp[a][b]);
while (a != parent[a])
{
b = a;
a = parent[a];
Min = min(Min, mp[a][b]);
}
a = edges.front().ff, b = edges.front().ss;
mp[a][b] -= Min;
mp[b][a] += Min;
while (a != parent[a])
{
b = a;
a = parent[a];
mp[a][b] -= Min;
mp[b][a] += Min;
}
rez += Min;
edges.pop();
}
}
return rez;
}
int main()
{
ios::sync_with_stdio(false);
fin.tie(NULL);
fout.tie(NULL);
int source, sink;
fin >> n >> m;
for (int i = 0; i < m; i++)
{
int a, b, w;
fin >> a >> b >> w;
mp[a][b] = w;
}
fout << edmondsKarp(1, n);
}