Cod sursa(job #1164952)

Utilizator DanutsDanut Rusu Danuts Data 2 aprilie 2014 13:07:50
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.92 kb
#include <cstdio>
#include <vector>
#include <queue>
#define maxn 100005
#define INF 999999
using namespace std;
FILE *f=fopen("bfs.in","r");
FILE *g=fopen("bfs.out","w");
vector <int> G[maxn],viz(maxn,0),d(maxn,INF);
queue <int> Q;
int n,m,s,x,y;
void bfs(int s){
    viz[s]=1;
    d[s]=0;
    Q.push(s);
    while(Q.empty()==0){
          int nod=Q.front();
          Q.pop();
          for(int i=0;i<G[nod].size();i++)
                if(viz[G[nod][i]]==0){
                        Q.push(G[nod][i]);
                        viz[G[nod][i]]=1;
                        d[G[nod][i]]=d[nod]+1;
                }
    }
}
int main()
{
    fscanf(f,"%d%d%d",&n,&m,&s);
    for(int i=1;i<=m;i++){
        fscanf(f,"%d%d",&x,&y);
        G[x].push_back(y);
    }
    bfs(s);
    for(int i=1;i<=n;i++)
        if(d[i]!=INF)
        fprintf(g,"%d ",d[i]);
        else
        fprintf(g,"-1 ");

    return 0;
}