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#include <vector>
#include <cstring>
#include <queue>
#include <fstream>
using namespace std;
ifstream fin ("maxflow.in");
ofstream fout ("maxflow.out");
const int Dim = 1005;
const int Inf = 0x3f3f3f3f;
vector < int > G[Dim];
int n,m;
int v[Dim],C[Dim][Dim],t[Dim];
int MaxFlow(int source, int sink);
int main() {
fin >> n >> m;
int x,y,w;
for ( int i = 1; i <= m; ++i) {
fin >> x >> y >> w;
G[x].push_back(y);
G[y].push_back(x);
C[x][y] += w; /// retinem costul intr-o matrice pentru a-l modifica mai usor
}
fout << MaxFlow(1,n) << "\n"; /// flux
}
bool Bf( int source, int snik) { /// facem lanturile si salvam tatii
memset(v,0,sizeof(v));
queue < int > Q;
Q.push(source);
v[source] = 1;
while (!Q.empty())
{
int x = Q.front();
Q.pop();
if (x == snik)
continue;
for (const auto& y : G[x])
if (!v[y] && C[x][y] > 0)
{
v[y] = 1;
t[y] = x;
Q.push(y);
}
}
return v[snik];
}
inline int MaxFlow(int source, int sink)
{
int maxflow = 0, fmin;
while (Bf(source, sink) ) {
for (const auto& x : G[sink])
{
if (!v[x] || C[x][sink] <= 0)
continue;
t[sink] = x;
fmin = Inf;
for (int i = sink ; i != source ; i = t[i])
fmin = min(fmin, C[t[i]][i]); /// minimul de pe lant
for (int i = sink ; i != source ; i = t[i])
{
C[t[i]][i] -= fmin; /// scadem capacitatea ocupata
C[i][t[i]] += fmin; /// adunam pe muchia inversa ca sa nu se strice bfs-ul
}
maxflow += fmin;
}
}
return maxflow;
}