Cod sursa(job #2263344)

Utilizator slym777Darii Dan slym777 Data 18 octombrie 2018 17:03:19
Problema BFS - Parcurgere in latime Scor 80
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1 kb
#pragma GCC optimize("O3")

#include <iostream>
#include <bits/stdc++.h>

using namespace std;

ifstream fin("bfs.in");
ofstream fout("bfs.out");

queue <int> Q;
vector <list < int > > L;
int vizitat[120000], dist[120000];

void BFS(int s)
{
    int x;
    Q.push(s);
    dist[s] = 0;
    vizitat[s] = 1;
    while (!Q.empty())
    {
        x = Q.front();
        Q.pop();
        for (auto a:L[x])
        {
            if (!vizitat[a])
            {
                Q.push(a);
                vizitat[a] = 1;
                dist[a] = dist[x] + 1;
            }
        }
    }
}

int main()
{
    ios_base::sync_with_stdio(0);
    fin.tie(0); fout.tie(0);

    int n,m,s,x,y;
    fin >> n >> m >> s;
    L.resize(n+1);
    for (int i = 0; i < m; i++)
    {
        fin >> x >> y;
        L[x].push_back(y);
    }
    BFS(s);
    for (int i = 1; i <= n; i++)
        if (!vizitat[i])
            fout << -1 << " ";
        else fout << dist[i] << " ";
    return 0;
}