Cod sursa(job #2365977)

Utilizator TyFrostbyteIon Robert-Gabriel TyFrostbyte Data 4 martie 2019 17:47:17
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.96 kb
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

vector<vector<unsigned int> > G;

vector<int> bfs(unsigned int n, unsigned int start){
    vector<bool> seen(n+1, false);
    seen[start]=true;
    vector<int> path(n+1, -1);
    path[start]=0;

    queue<unsigned int> q;
    q.push(start);

    while(!q.empty()) {
        unsigned int node = q.front();

        for (unsigned int v : G[node]) {
            if (!seen[v]) {
                seen[v] = true;
                q.push(v);
            }
        }

        q.pop();
    }

    return path;
}

int main() {
    unsigned int n, m, s;
    fin >> n >> m >> s;
    G = vector<vector<unsigned int> >(n + 1);
    for (unsigned int i = 0; i < m; i++) {
        unsigned int x, y;
        fin >> x >> y;
        G[x].push_back(y);
    }

    vector<int> path = bfs(n, s);
    for (int i = 1; i <= n; i++)
        fout << path[i] << " ";

    return 0;
}