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#include<fstream>
#include<iostream>
#include<vector>
#include <cstring>
#define INF 0x3f3f3f3f
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
int n,m,k,i,j,p,x,y,t,cap,flux,fmin;
int C[1024][1024],F[1024][1024],coada[1024],viz[1024],precedent[1024];
///F[i][j] = fluxul curent dintre nodul i si j
///C[i][j] = capacitatea dintre nodul i si j
vector <int> v[1024];
vector <int> frunze;
bool bfs()
{
int nod, i, vecin,dr,st;
st=dr=1;
coada[st] = 1;
viz[1] = 1;
for(i=2;i<=n;i++)
{
viz[i] = 0;
}
while(st <= dr)
{
nod = coada[st];
for(i=0;i<v[nod].size();i++)
{
vecin = v[nod][i];
if(viz[vecin] == 0 and C[nod][vecin] != F[nod][vecin]) //daca muchia nu este saturata
{
dr++;
coada[dr] = vecin;
viz[vecin] = 1;
precedent[vecin] = nod;
if(vecin == n)
return true;
}
}
st++;
}
return false;
}
int main()
{
fin >> n >> m;
for(i=1;i<=m;i++)
{
fin>>x>>y>>cap;
C[x][y] += cap;
v[x].push_back(y);
v[y].push_back(x);
if(y == n)
{
frunze.push_back(x);
}
}
flux = 0;
///cand nu mai gasim drum de la sursa la destinatie inseamna ca fluxul este maxim
while(bfs() == true)
//bfs();
{
for(j = 0; j < frunze.size(); j++)
{
int nod = frunze[j];
if(C[nod][n] != F[nod][n])
{
precedent[n] = nod;
//fout << nod << "\n";
fmin = INF;
nod = n;
//fmin = min(fmin, C[nod][n] - F[nod][n]);
while(nod != 1)
{
fmin = min(fmin, C[precedent[nod]][nod] - F[precedent[nod]][nod]);
nod = precedent[nod];
}
nod = n;
while(nod != 1)
{
F[precedent[nod]][nod] += fmin;
F[nod][precedent[nod]] -= fmin;
nod = precedent[nod];
}
flux = flux + fmin;
}
}
/*fmin = INF;
int nod = n;
///selectam cantitatea minima de flux disponibila de pe augmenting path-ul gasit
while(nod != 1)
{
fmin = min(fmin, C[precedent[nod]][nod] - F[precedent[nod]][nod]);
nod = precedent[nod];
}
nod = n;
///updatam cantitatea de flux de pe drumul parcurs
while(nod != 1)
{
F[precedent[nod]][nod] += fmin;
F[nod][precedent[nod]] -= fmin;
nod = precedent[nod];
}
flux = flux + fmin;
*/
}
fout << flux << "\n";
}