Cod sursa(job #1060228)

Utilizator nicnic28nichita trita nicnic28 Data 17 decembrie 2013 19:15:23
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.76 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
using namespace std;
fstream in("bfs.in",ios::in),out("bfs.out",ios::out);
const int N=100005;
int n,m,s,c[N];
queue<int> q;
vector<int> a[N];
void bfs(int s){
    q.push(s);
    c[s]=0;
    while(!q.empty()){
        int p=q.front();
        q.pop();
        for(int i=0 ; i<a[p].size() ; i++){
            if(c[a[p][i]]==-1){
                c[a[p][i]]=c[p]+1;
                q.push(a[p][i]);
            }
        }
    }
}
int main()
{
    in>>n>>m>>s;
    int x,y;
    while(in>>x>>y){
        a[x].push_back(y);
    }
    for(int i=1 ; i<=n ; i++){
        c[i]=-1;
    }
    bfs(s);
    for(int i=1 ; i<=n ; i++){
        out<<c[i]<<' ';
    }
    return 0;
}