Cod sursa(job #3296967)

Utilizator Horia14Horia Banciu Horia14 Data 19 mai 2025 17:02:17
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.03 kb
#include <fstream>
#include <vector>
#include <queue>
#define MAX_NODES 100000

using namespace std;

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

vector<int> g[MAX_NODES + 1];
int dist[MAX_NODES + 1];
int n, m, S;

void BFS(int source) {

    int currNode;
    queue<int> q;

    for (int i = 0; i <= n; ++i) {
        dist[i] = -1;
    }

    dist[source] = 0;

    q.push(source);

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

        for (auto neighbour : g[currNode]) {
            if (dist[neighbour] == -1) {
                dist[neighbour] = 1 + dist[currNode];
                q.push(neighbour);
            }
        }
    }
}

void readGraph() {
    fin >> n >> m >> S;
    int x, y;

    for (int i = 0; i < m; ++i) {
        fin >> x >> y;
        g[x].push_back(y);
    }

    fin.close();
}

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

    fout << "\n";
    fout.close();
}


int main() {
    readGraph();
    BFS(S);
    printSolution();
    return 0;
}