Cod sursa(job #1657818)

Utilizator pitradaPit-Rada Ionel-Vasile pitrada Data 20 martie 2016 20:19:41
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.67 kb
#include<fstream>
using namespace std;
ifstream  fin("bellmanford.in");
ofstream fout("bellmanford.out");
struct nod2
{
    int vecin,cost;
    nod2 *leg;
};

nod2 *LV[50002], *p;
int N,M,d[50002], coada[50001], pr, ul, nrcoada, i, x, y, c, nr[50002], ok;
char viz[50002];
int main()
{
    fin>>N>>M;
    for(i=1;i<=M;i++)
    {
        fin>>x>>y>>c;
        p=new nod2;
        p->vecin=y;
        p->cost=c;
        p->leg=LV[x];
        LV[x]=p;
    }
    for(i=1;i<=N;i++)
    {
        d[i]=1000000000;
        viz[i]=0;
    }
    d[1]=0;
    coada[1]=1;
    pr=1;
    ul=1;
    nrcoada=1;
    viz[1]=1;
    ok=1;
    while(nrcoada>0)
    {
        x=coada[pr];
        nr[x]++;
        if(nr[x]>N){
            ok=0;
            break;
        }
        for(p=LV[x];p;p=p->leg)
        {
            y=p->vecin;
            c=p->cost;
            if(d[x]+c<d[y])
            {
                d[y]=d[x]+c;
                if(viz[y]==0)
                {
                    viz[y]=1;
                    ul++;
                    if(ul>N)
                    {
                        ul=1;
                    }
                    coada[ul]=y;
                    nrcoada++;
                }
            }
        }
        viz[x]=0;
        pr++;
        if(pr>N)
        {
            pr=1;
        }
        nrcoada--;
    }
    if(ok==0){
        fout<<"Ciclu negativ!";
    }
    else{
        for(i=2;i<=N;i++)
        {
            if(d[i]==1000000000)
            {
                d[i]=0;
            }
            fout<<d[i]<<" ";
        }
    }
    fout.close();
    fin.close();
    return 0;
}