Cod sursa(job #2787487)

Utilizator DananauStefanRazvanDananau Stefan-Razvan DananauStefanRazvan Data 23 octombrie 2021 14:35:14
Problema BFS - Parcurgere in latime Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.96 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

#define maxN 100001

int n, m, start;
vector<vector<int>> adj;
vector<int> dist;
queue<int> q;

void citire() {
    fin >> n >> m >> start;

    adj.resize(n + 1);

    for (int i = 0; i < m; i++) {
        int a, b;
        fin >> a >> b;
        adj[a].push_back(b);
    }
}

void bfs() {
    dist.resize(n);

    for (int i = 1; i <= n; i++)///i = 1
        dist[i] = -1;

    int nod = start;
    q.push(nod);
    dist[nod] = 0;

    while (!q.empty()) {
        nod = q.front();
        q.pop();
        for (auto i : adj[nod])
            if (dist[i] == -1) {
                dist[i] = dist[nod] + 1;
                q.push(i);
            }
    }

    for (int i = 1; i <= n; i++)
        fout << dist[i] << " ";
}
int main() {

    citire();
    bfs();

    return 0;
}