Cod sursa(job #341667)

Utilizator AstronothingIulia Comsa Astronothing Data 19 august 2009 10:39:40
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.74 kb
#include <fstream>
#include <queue>
#include <vector>

using namespace std;

int main()
{
    ifstream f("bfs.in");
    ofstream f2("bfs.out");
    int n,m,s,x,y;
    f>>n>>m>>s;
    --s;
    vector<int> v[100001];
    int res[100001];
    memset(res,-1,sizeof(res));
    while(m--)
    {
        f>>x>>y;
        v[x-1].push_back(y-1);
    }
    res[s] = 0;
    queue<int> q;
    q.push(s);
    while(!q.empty())
    {
        int crt = q.front();
        q.pop();
        for(int i=0;i<v[crt].size();++i)
            if(res[v[crt][i]]==-1)
            {
                res[v[crt][i]] = res[crt]+1;
                q.push(v[crt][i]);
            }
    }

    for(int i=0;i<n;++i) f2<<res[i]<<" ";
    return 0;
}