Cod sursa(job #1789362)

Utilizator RaduMirceaAndreiRadu Mircea Andrei RaduMirceaAndrei Data 26 octombrie 2016 21:57:34
Problema Flux maxim Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.51 kb
# include <fstream>
# include <vector>
# include <deque>
# include <cstring>
# define DIM 1010
# define pb push_back
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
vector <int> Lista[DIM];
deque <int> d;
int c[DIM][DIM],f[DIM][DIM],Marcat[DIM],t[DIM];
int n,m,i,j,x,y,cost,mn,nc,sol;
int bfs(){
    memset(Marcat,0,sizeof(Marcat));
    int ok=0;
    d.pb(1);
    Marcat[1]=1;
    while(!d.empty()){
        int nc=d.front();
        d.pop_front();
        if(nc==n)
            ok=1;
        for(int i=0;i<Lista[nc].size();i++){
            int nv=Lista[nc][i];
            if(Marcat[nv]==0&&f[nc][nv]<c[nc][nv]){
                Marcat[nv]=1;
                t[nv]=nc;
                d.pb(nv);
            }
        }
    }
    return ok;
}
int main () {
    fin>>n>>m;
    for(i=1;i<=m;i++){
        fin>>x>>y>>cost;
        Lista[x].pb(y);
        Lista[y].pb(x);
        c[x][y]=cost;
    }
    while(bfs()){
        for(j=0;j<Lista[n].size();j++){
            nc=Lista[n][j];
            if(Marcat[nc]&&c[nc][n]-f[nc][n]>0){
                mn=c[nc][n]-f[nc][n];
                for(i=nc;t[i]!=0;i=t[i])
                    mn=min(mn,c[t[i]][i]-f[t[i]][i]);
                f[nc][n]+=mn;
                f[n][nc]-=mn;
                for(i=nc;t[i]!=0;i=t[i]){
                    f[t[i]][i]+=mn;
                    f[i][t[i]]-=mn;
                }
                sol+=mn;
            }
        }
    }
    fout<<sol<<"\n";
    return 0;
}