Cod sursa(job #1754374)

Utilizator AlexVolatiluVoicu Alex AlexVolatilu Data 8 septembrie 2016 00:15:03
Problema Flux maxim Scor 60
Compilator cpp Status done
Runda Arhiva educationala Marime 1.33 kb
#include <stdio.h>
#include <queue>
#include <vector>
#include <string.h>

#define inf 2000000000

using namespace std;

int c[1005][1005],f[1005][1005];
int t[1005],n,m;
vector<int> vecini[1005];

int bfs()
{
    queue<int> q;
    int a,b,i,j;
    memset(t,0,sizeof(t));
    t[1]=-1;
    q.push(1);
    while(!q.empty())
    {
        a=q.front();
        q.pop();
        for(i=0,j=vecini[a].size(); i<j; i++)
        {
            b=vecini[a][i];
            if(!t[b]&&c[a][b]>f[a][b])
            {
                q.push(b);
                t[b]=a;
                if(b==n) return 1;
            }
        }
    }
    return 0;
}

int main()
{
    freopen("maxflow.in","r",stdin);
    freopen("maxflow.out","w",stdout);
    int i,j,v1,v2,v3,fluxm=0;
    scanf("%d%d",&n,&m);
    for(i=0; i<m; i++)
    {
        scanf("%d%d%d",&v1,&v2,&v3);
        c[v1][v2]=v3;
        vecini[v1].push_back(v2);
    }

    while(bfs())
    {
        v1=inf;
        i=n;
        while(i!=1)
        {
            v1=v1<(c[t[i]][i]-f[t[i]][i]) ? v1 : (c[t[i]][i]-f[t[i]][i]);
            i=t[i];
        }
        i=n;
        while(i!=1)
        {
            f[t[i]][i]+=v1;
            f[i][t[i]]-=v1;
            i=t[i];
        }
        fluxm+=v1;
    }
    printf("%d",fluxm);
    return 0;
}