Cod sursa(job #2333010)

Utilizator AndreiDeltaBalanici Andrei Daniel AndreiDelta Data 31 ianuarie 2019 16:39:08
Problema Flux maxim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.54 kb
#include <bits/stdc++.h>
#define Dim 1003
using namespace std;
ifstream f("maxflow.in");
ofstream g("maxflow.out");
int N,M,a,b,c,flow;
int C[Dim][Dim],T[Dim];
bool viz[Dim];

vector < int > V[Dim];

bool BFS()
{
    queue <int> qu;
    qu.push(1);
    T[1]=1;
    viz[1]=1;
    while(!qu.empty()&&!viz[N])
    {
        int nod=qu.front();
        qu.pop();
        for(unsigned int i=0;i<V[nod].size();i++)
      {
        int vecin=V[nod][i];
        int cap=C[nod][vecin];
        if(cap>0&&!viz[vecin])
        {
            T[vecin]=nod;
            qu.push(vecin);
            viz[vecin]=1;
        }
      }

    }
    return viz[N];
}

void init()
{
    for(int i=1;i<=N;i++)
    {
        viz[i]=0;
        T[i]=0;
    }
}

int main()
{
    f>>N>>M;
    for(int i=1;i<=M;i++)
    {
        f>>a>>b>>c;
        C[a][b]=c;
        V[a].push_back(b);
        V[b].push_back(a);
    }
    while(BFS())
    {
        for(unsigned int i=0;i<V[N].size();i++)
        if(viz[V[N][i]]==1&&C[V[N][i]][N]>0)
        {
            int minim=INT_MAX;
            T[N]=V[N][i];
            int poz=N;
            while(poz!=1)
            {
                minim=min(minim,C[T[poz]][poz]);
                poz=T[poz];
            }
            poz=N;
            while(poz!=1)
            {
                C[T[poz]][poz]-=minim;
                C[poz][T[poz]]+=minim;
                poz=T[poz];
            }
            flow+=minim;
        }
        init();
    }
    g<<flow;
    return 0;
}