Cod sursa(job #3227472)

Utilizator adimiclaus15Miclaus Adrian Stefan adimiclaus15 Data 1 mai 2024 09:44:02
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.13 kb
#include <bits/stdc++.h>

using namespace std;

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

const int NMAX = 1e5;
const int INF = 1e9;
vector<int> G[NMAX + 1];
queue<int> q;
int d[NMAX + 1], vis[NMAX + 1];
int n, m, start;

void bfs(int s) {
    //d[i] = distanta de la nodul s la nodul i
    for(int i = 1; i <= n; i++) {
        d[i] = INF;
    }
    d[s] = 0;
    q.push(s);
    vis[s] = 1;
    while(!q.empty()) {
        int node = q.front();
        q.pop();
        for(int i = 0; i < G[node].size(); i++) {
            int vecin = G[node][i];
            if(!vis[vecin] && d[vecin] > d[node] + 1) {
                d[vecin] = d[node] + 1;
                vis[vecin] = 1;
                q.push(vecin);
            }
        }
    }
}

int main() {
    
    f >> n >> m >> start;
    for(int i = 1; i <= m; i++) {
        int x, y;
        f >> x >> y;
        G[x].push_back(y);
        //G[y].push_back(x); //daca avem un graf orientat linia asta dispare
    }
    bfs(start);
    for(int i = 1; i <= n; i++) {
        if(d[i] == INF) {
            g << -1 << ' ';
        } else {
            g << d[i] << ' ';
        }
    }
    return 0;
}