Cod sursa(job #2445578)

Utilizator blotucosmincosmin blotucosmin Data 4 august 2019 18:35:12
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.8 kb
#include <fstream>
#include <vector>
#include <queue>
#include <iostream>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
vector <int> v[100001];
queue <int> Q;
int viz[100001],n,m,x,y,s;
void bfs()
{
    Q.push(s);
    viz[s]=0;
    while(!Q.empty())
    {
        int x=Q.front();
        Q.pop();
        for(vector<int> :: iterator it = v[x].begin(); it != v[x].end(); ++ it)
            if(viz[*it] == -1)
            {
                viz[*it]=viz[x]+1;
                Q.push(*it);
            }
    }
}
int main()
{
    fin>>n>>m>>s;
    while(m--)
    {
        fin>>x>>y;
        v[x].push_back(y);
    }
    for(int i = 1; i <= n; ++ i)
        viz[i] = -1;
    bfs();
    for(int i = 1; i <= n; ++ i)
        fout << viz[i] << " ";
    return 0;
}