Cod sursa(job #1209114)

Utilizator TarabanDragosTaraban Dragos-Petru TarabanDragos Data 17 iulie 2014 03:30:32
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1 kb
#include<cstdio>
#include<vector>
using namespace std;
vector< pair<int,int> >L[50010];
int n,m,i,j,p,u,a,b,q,v[50010],x[50010],c[1000000];
FILE *f,*g;
int main(){
    f=fopen("bellmanford.in","r");
    g=fopen("bellmanford.out","w");
    fscanf(f,"%d%d",&n,&m);
    for(i=1;i<=m;i++){
       fscanf(f,"%d%d%d",&a,&b,&q);
       L[a].push_back(make_pair(b,q));
    }
    for(i=2;i<=n;i++){
        v[i]=2000000000;
    }
    p=u=1;
    c[u]=1;
    while(p<=u){
        a=c[p];
        x[a]++;
        if(x[a]==n){
            fprintf(g,"Ciclu negativ!");
            return 0;
        }
        else{
            for(i=0;i<L[a].size();i++){
                if(v[ L[a][i].first ]>v[a]+L[a][i].second){
                    v[ L[a][i].first ]=v[a]+L[a][i].second;
                    c[++u]=L[a][i].first;
                }
            }
        }
        p++;
    }
    for(i=2;i<=n;i++){
        fprintf(g,"%d ",v[i]);
    }



    fclose(f);
    fclose(g);
    return 0;
}