Cod sursa(job #3354461)

Utilizator cont_superscoalaSuperScoala cont_superscoala Data 18 mai 2026 13:04:32
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.99 kb
/*
https://infoarena.ro/problema/bfs
*/
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

void bfs(int x0, vector < vector <int>> &l_s, vector <int> &d)
{
    fill(d.begin(), d.end(), -1);
    queue <int> q;
    q.push(x0);
    d[x0] = 0;
    while (!q.empty())
    {
        int x = q.front();
        q.pop();
        for (auto y: l_s[x])
        {
            if (d[y] == -1)
            {
                q.push(y);
                d[y] = 1 + d[x];
            }
        }
    }
}

int main()
{
    ifstream in("bfs.in");
    ofstream out("bfs.out");
    int n, m, s;
    in >> n >> m >> s;
    vector < vector <int>> l_s(n + 1);
    for (int i = 0; i < m; i++)
    {
        int x, y;
        in >> x >> y;
        l_s[x].push_back(y);
    }
    in.close();
    vector <int> d(n + 1);
    bfs(s, l_s, d);
    for (int i = 1; i <= n; i++)
    {
        out << d[i] << " ";
    }
    out << "\n";
    out.close();
    return 0;
}