Cod sursa(job #2301054)

Utilizator YouDontNeedMyNameJurcut Paul YouDontNeedMyName Data 12 decembrie 2018 16:17:15
Problema Flux maxim Scor 60
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <bits/stdc++.h>
#define N 1005
using namespace std;
ifstream in("maxflow.in");
ofstream out("maxflow.out");
int n,m,pater[N],graph[N][N],Rgraph[N][N],ap[N];
deque <int> q;
bool BFS(int node)
{
    memset(pater,-1,sizeof(pater));
    memset(ap,0,sizeof(ap));
    pater[node]=0;
    q.push_back(node);
    while(!q.empty())
    {
        int p=q.front();
        q.pop_front();
        for(int i=1; i<=n; i++)
        {
            if(graph[p][i]>0 && !ap[i])
            {
                pater[i]=p;
                ap[i]=1;
                q.push_back(i);
            }
        }
    }
    if(ap[n])
        return true;
    return false;
}
int main()
{
    in >> n >> m;
    for(int i=1; i<=m; i++)
    {
        int x,y;
        in >> x >> y;
        in >> graph[x][y];
    }
    int max_flow=0;
    while(BFS(1))
    {
        int current_flow=99999999;
        for(int i=n; i!=1; i=pater[i])
        {
            int j=pater[i];
            current_flow=min(current_flow,graph[j][i]);
        }
        for(int i=n; i!=1; i=pater[i])
        {
            int j=pater[i];
            graph[j][i]-=current_flow;
            graph[i][j]+=current_flow;
        }
        max_flow+=current_flow;
    }
    out << max_flow;
    return 0;
}