Cod sursa(job #2673583)

Utilizator valentinchipuc123Valentin Chipuc valentinchipuc123 Data 17 noiembrie 2020 11:17:40
Problema Flux maxim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

ifstream f("maxflow.in");
ofstream g("maxflow.out");

int n,m,val[1005][1005],cap[1005][1005],tata[1005],drum[1005];
bool fost[1005];
vector<int>vecini[1005];

bool arb()
{
 for(int i=1;i<=n;i++) fost[i]=0;
 int nr=1; drum[1]=1; fost[1]=1;

 for(int i=1;i<=nr;i++)
 {
   int nod=drum[i];

   if( nod==n )
    continue;

   for(int j=0;j<vecini[nod].size();j++)
   {
     int x=vecini[nod][j];

     if( fost[x]||cap[nod][x]==val[nod][x] ) continue;
     fost[x]=1;
     tata[x]=nod;
     drum[++nr]=x;
   }
 }

 return fost[n];
}

int main()
{
 f>>n>>m;
 for(int i=1;i<=m;i++)
 {
  int x,y,z;
  f>>x>>y>>z;
  val[x][y]=z;
  vecini[x].push_back(y);
  vecini[y].push_back(x);
 }

 int fluxmax=0,flux=0;

 while( arb() )
 {
   for(int i=0;i<vecini[n].size();i++)
   {
     flux=100000000;
     int nod=vecini[n][i];

     if( !fost[nod]||cap[nod][n]==val[nod][n] ) continue;

     tata[n]=nod;
     for(int j=n ; j!=1 ; j=tata[j]) flux=min(flux,val[tata[j]][j]-cap[tata[j]][j]);

     if( flux==0 ) continue;

     for(int j=n ; j!=1 ; j=tata[j]){
       cap[tata[j]][j]+=flux;
       cap[j][tata[j]]-=flux;
     }

     fluxmax+=flux;
   }
 }
 g<<fluxmax;
}