Cod sursa(job #1830487)

Utilizator snappyRazvan Alin snappy Data 16 decembrie 2016 19:40:17
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.73 kb
#include <fstream>
#include <vector>
#include <queue>
#define pb push_back

using namespace std;

const int N = 100005;

ifstream f("bfs.in");
ofstream g("bfs.out");

vector<int> v[N];
queue<int> q;
int d[N];
int n, m, s, x, y, i;

void bfs(int);

int main() {

    f >> n >> m >> s;
    for(; m; m--) {
        f >> x >> y;
        v[x].pb(y);
    }

    bfs(s);

    for(i = 1; i <= n; i++)
        g << d[i] - 1 << ' ';

    return 0;
}

void bfs(int source) {
    d[source] = 1;
    q.push(source);

    while(!q.empty()) {
        int x = q.front(); q.pop();

        for(auto it : v[x])
            if(!d[it]) {
                d[it] = d[x] + 1;
                q.push(it);
            }
    }
}