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//program 3.4 Flux maxim
#include <fstream>
#include <iostream>
#include <queue>
using namespace std;
int a[1001][1001], c[1001][1001], f[1001][1001];
int viz[1001],T[1001];
int n,m,lung,minim;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
struct arc{int n1,n2;};
arc drum[101];
int bf()
{
int i,j;
queue <int> q;
fill(viz,viz+101,0);fill(T,T+101,0);
q.push(1);
viz[1] = 1;
while (q.empty() != 1)
{ i = q.front();
if (i == n)
return 1;
q.pop();
for (j = 1;j<=n;j++)
{ if (viz[j] == 0 && c[i][j] - f[i][j] > 0)
{//arc parcurs in sens direct
viz[j] = 1;
T[j] = i;
q.push(j);
}
if (viz[j] == 0 && f[j][i] > 0)
{//arc parcurs in sens invers
viz[j] = 1;
T[j] = i;
q.push(j);
}
}
}
return 0;
}
void calcdrum()
{
int i=0,b=n,a;
minim = 10000000;
a = T[b];
while (a!=0)
{
drum[i].n1 = a;
drum[i].n2 = b;
if (c[a][b] > f[a][b])
{if (minim > c[a][b] - f[a][b])
minim = c[a][b] - f[a][b];
}
else
if (minim > f[b][a])
minim = f[b][a];
i++;
b = a;
a = T[b];
}
lung = i;
}
int main()
{
int i,j,k,ok=1;
fin >> n >> m;
for (i=0;i<m;i++)
{fin >> i >> j;
fin >> c[i][j];
}
while (ok == 1)
{
ok=bf(); //returneaza 1 daca gaseste un drum
if (ok == 1)
{ calcdrum(); //calculeaza si minimul
/*
cout<<"\n\ngasit un drum de lungime "<< lung;
cout<<" capacitate reziduala "<< minim << endl;
cout << "format din arcele: ";
*/
for (k=0;k<lung;k++)
{ i = drum[k].n1;
j = drum[k].n2;
// cout<< i << '-' << j << " , ";
if (c[i][j] - f[i][j] > 0)
f[i][j] += minim;
else
f[j][i] -= minim;
}
}
}
int fluxmax = 0;
for (i=1;i<=n;i++)
fluxmax += f[1][i];
// cout<<"\n\nflux maxim= "
fout<<fluxmax<<endl;
/*
cout<<"starea fiecarui arc:capacitate/flux\n";
for (i=1;i<=n;i++)
for (j=1;j<=n;j++)
if (c[i][j]>0)
{ cout<<'('<<i<<'-'<<j<<"):";
cout<<c[i][j]<<'/'<<f[i][j]<<endl;
}
*/
return 0;
}