Cod sursa(job #1217336)

Utilizator AeroHHorea Stefan AeroH Data 7 august 2014 03:19:26
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.67 kb
#include <fstream>
#include <vector>
#include <queue>
#define NMAX 1000005
//#define punct pair<int,int>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");

int N,M,i,S,d[NMAX],x,y;
queue<int> Q;
vector<int> v[NMAX];
int main()
{
    f>>N>>M>>S;
    while(M--)f>>x>>y,v[x].push_back(y);

    for (i=1;i<=NMAX;++i)
        d[i]=-1;
    d[S]=0;

    Q.push(S);
    while(!Q.empty())
        {
            int cr=Q.front();Q.pop();
            for (i=0;i<v[cr].size();++i)
                if (d[v[cr][i]]==-1)
                    d[v[cr][i]]=d[cr]+1,Q.push(v[cr][i]);
        }
    for(i=1;i<=N;++i)
        g<<d[i]<<" ";



    return 0;
}