Cod sursa(job #2210412)

Utilizator Dragos101Baciu Dragos Dragos101 Data 6 iunie 2018 17:24:04
Problema BFS - Parcurgere in latime Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 0.84 kb
#include <fstream>

using namespace std;

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

bool a[1002][1002];
int n, m, s, d[1003];
int q[100003], pr, ul;

void BFS(int s)
{
    int i, x;
    pr = 0;
    ul = -1;
    q[++ul] = s;
    for(i = 1; i <= n; i++)
        d[i] = -1;
    d[s] = 0;
    while(pr <= ul)
    {
        x = q[pr];
        pr++;
        for(i = 1; i <= n; i++)
            if(a[x][i] == true)
                if(d[i] > d[x] + 1 || d[i] == -1)
                {
                    d[i] = d[x] + 1;
                    q[++ul] = i;
                }
    }
}

int main()
{
    int i, x, y;
    fin >> n >> m >> s;
    for(i = 1; i <= m; i++)
    {
        fin >> x >> y;
        a[x][y] = true;
    }
    BFS(s);
    for(i = 1; i <= n; i++)
        fout << d[i] << " ";
    return 0;
}