Cod sursa(job #1153788)

Utilizator sorynsooSorin Soo sorynsoo Data 25 martie 2014 18:52:11
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.87 kb
#include <fstream>
#include <vector>
#include <queue>
#define infinit 999999
using namespace std;
ifstream cin("bfs.in");
ofstream cout("bfs.out");
vector<int> graf[100001];
queue<int> coada;
int i,j,x,y,n,m,drum[100001],s,ok;
int main()
{
    cin>>n>>m>>s; //n=nr noduri, m=nr muchii
    for(i=1; i<=m; i++)
    {
        cin>>x>>y;
        graf[x].push_back(y);
    }
    for(i=1; i<=n; i++)
        drum[i]=infinit;
    coada.push(s); drum[s]=0;
    while(!coada.empty())
    {
        ok=coada.front(); coada.pop();
        for(int i=0; i<graf[ok].size(); i++)
            if(drum[graf[ok][i]]>drum[ok]+1)
            {
                drum[graf[ok][i]]=drum[ok]+1;
                coada.push(graf[ok][i]);
            }
    }
    for(i=1; i<=n; i++)
        if(drum[i]==infinit)
            cout<<"-1 ";
        else
            cout<<drum[i]<<" ";

}