Cod sursa(job #2486724)

Utilizator pro119Manea Dumitru pro119 Data 3 noiembrie 2019 13:45:21
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.99 kb
#include <bits/stdc++.h>
using namespace std;


vector <int> v[100005];
queue <int> q;
long n,m,s,a,b,dist[100005];
void bfs(long start)
{
    q.push(start);
    while(!q.empty())
    {
        int k=q.front();
        q.pop();
        for (int i=0; i<v[k].size(); i++)
            if (dist[v[k][i]]==0 && v[k][i]!=start){
                dist[v[k][i]]=dist[k]+1;
                q.push(v[k][i]);
            }
    }
}

int main()
{
    ifstream cin("bfs.in");
    ofstream cout("bfs.out");
    cin>>n>>m>>s;
    for (int i=1; i<=m; i++)
    {
        cin>>a>>b;
        v[a].push_back(b);
    }
    bfs(s);
    for (int i=1; i<=n; i++)
    {
        if(i==s) cout << 0 <<" " ;
        else if (dist[i]==0) cout << -1<<" ";
        else cout << dist[i]<<" ";
    }
    return 0;
}
/*
    for(int i=1; i<=n; i++)
    {
        cout<<i<<":";
        for(int j=0; j<v[i].size(); j++){
           cout<<" "<<v[i][j]<<" ";
        }
        cout <<"\n";
    }
    */