Cod sursa(job #626129)

Utilizator GabiiRus Gabriela Gabii Data 26 octombrie 2011 14:19:59
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.05 kb
# include <fstream>
# include <vector>
using namespace std;
int viz[100005],n,m,x,y,cont=1,c[100001];
double long k,cost[100001];
vector <int> A[100001];
ofstream g("bfs.out");
void citire_graf()
{
     ifstream f("bfs.in");
     int x,y;
     f>>n>>m>>k;
     int i;
     for (i=1;i<=m;i++)
     {
         f>>x>>y;
         A[x].push_back(y);
     }
     f.close();
}

void bfs(int k)
{
     int li,ls,i,nr_vecini,nod;
     li=1;
     ls=1;
     c[li]=k;
     viz[k]=1;
     while (li<=ls)
         {nod=c[li];
         nr_vecini=A[nod].size();
         for (i=0;i<nr_vecini;i++)
            if (viz[A[nod][i]]==0)
                 {ls++;
                 c[ls]=A[nod][i];
                 viz[A[nod][i]]=1;
                 cost[A[nod][i]]=cost[nod]+1;
                 }
          li++;
          }
}

int main()
{
     int i;
     citire_graf();
     bfs(k);
     for (i=1;i<=n;i++)
        if (cost[i]!=0 || i==k)  g<<cost[i]<<" ";
        else g<<-1<<" ";
        
     g.close();
     return 0;
}