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#include <bits/stdc++.h>
#include <iostream>
#include <fstream>
#include <climits>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
int N, M, s, f;
vector<int> tata;
vector<vector<int>> capacitate;
vector<vector<int>> Rcapac; // copie a grafului pentru rezidual
vector<vector<int>> LA;
void dfs() // dfs ca sa gasesc nodurile accesibile din s
{
vector<bool> viz(N + 1);
viz[s] = true;
for (int i = 0; i < M; i++)
if (capacitate[s][i] && !viz[i])
dfs();
}
bool bfs()
{
vector<bool> viz(N + 1);
queue<int> q;
q.push(s);
viz[s] = true;
tata[s] = -1;
while (!q.empty())
{
int u = q.front();
q.pop();
for (auto v : LA[u])
{
if (viz[v] == false && capacitate[u][v] != 0)
{
tata[v] = u;
if (v == f)
return true;
viz[v] = true;
q.push(v);
}
}
}
return false;
}
int EdmondsKarp()
{
int u, v;
for (u = 0; u < M; u++)
for (v = 0; v < M; v++)
Rcapac[u][v] = capacitate[u][v];
long max_flow = 0;
long max_flow = 0;
while (bfs())
{
int u, v;
int path_flow = INT_MAX;
for (v = f; v != s; v = tata[v])
{
// gasesc flow ul necesar ca sa nu se creeze bottleneck
u = tata[v];
path_flow = min(path_flow, capacitate[u][v]);
}
for (v = f; v != s; v = tata[v])
{
u = tata[v];
capacitate[u][v] -= path_flow; // scad flowul gasit din capacitate pe arcele normale
capacitate[v][u] += path_flow; // adun flow ul gasit pe arcele reverse
}
max_flow += path_flow; // adaug flowul gasit la total
}
/* pct b
//flowul e maxim atm, gasesc nodurile accesibile pornind din s
bool visited[M];
memset(visited, false, sizeof(visited));
dfs();
//afisez toate muchiile care leaga un nod accesibil de un nod izolat in grafic
for(int i=0; i<M; i++)
for(int j=0;j<M; j++)
if(visited[i] && !visited[j] && Rcapac[i][j])
cout<< i <<" - "<<j<<endl;
*/
return max_flow;
}
int main()
{
fin >> N >> M;
s = 1;
f = N;
LA.resize(N + 1);
tata.resize(N + 1);
capacitate.resize(N + 1, vector<int>(N + 1));
for (int i = 1; i <= M; i++)
{
int u, v;
long c;
fin >> u >> v >> c;
LA[u].push_back(v);
LA[v].push_back(u);
capacitate[u][v] = c;
}
fout << EdmondsKarp();
return 0;
}