Cod sursa(job #2972083)

Utilizator AlbuDariusAlbu Darius AlbuDarius Data 28 ianuarie 2023 17:39:16
Problema BFS - Parcurgere in latime Scor 80
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.85 kb
#include <fstream>

using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
int n, m, X, a[2][200001], start[100001], c[100001], d[100001];
void bfs(int nod)
{
    int x, ps = 1, pi = 1;
    d[nod] = 1;
    c[ps] = nod;
    while (ps <= pi) {
        x = start[c[ps]];
        while (x) {
            if (d[a[0][x]] == 0) {
                c[++pi] = a[0][x];
                d[a[0][x]] = d[c[ps]] + 1;
            }
            x = a[1][x];
        }
        ps++;
    }
}
int main()
{
    int i, x, y, k = 0;
    fin >> n >> m >> X;
    for (i = 1; i <= m; i++) {
        fin >> x >> y;
        if (x != y) {
            k++;
            a[0][k] = y;
            a[1][k] = start[x];
            start[x] = k;
        }
    }
    bfs(X);
    for (i = 1; i <= n; i++)
        fout << d[i] - 1 << " ";
    return 0;
}