Cod sursa(job #2375693)

Utilizator Cristian.BBurghelea Cristian Cristian.B Data 8 martie 2019 11:35:03
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.72 kb
#include <bits/stdc++.h>

using namespace std;

ifstream f ("bfs.in");
ofstream g ("bfs.out");

int n,m,s,x,y;
int root[100005];
vector<int> v[100005];
queue <int> q;

void BFS(int nod)
{
    q.push(nod);
    int p=1,u=1;
    while(!q.empty()){
        int x=q.front();
        q.pop();
        for(auto t:v[x])
            if(!root[t] && t!=nod){
                root[t]=root[x]+1;
                q.push(t);
            }
    }
}

int main()
{
    f>>n>>m>>s;
    for(int i=1;i<=m;++i){
        f>>x>>y;
        v[x].push_back(y);
    }
    BFS(s);

    for(int i=1;i<=n;++i)
        if(!root[i] && i!=s)g<<-1<<' ';
        else g<<root[i]<<' ';

    f.close(); g.close();
    return 0;
}