Cod sursa(job #2808010)

Utilizator truscalucaLuca Trusca truscaluca Data 24 noiembrie 2021 14:17:09
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 2.32 kb
#include <iostream>
#include <list>
#include <queue>
#include <vector>
#include <fstream>

using namespace std;

const int nMax = 100005;

class Graf {
private:
    int m_n, m_m;
    list<int> m_listAd[nMax];

    // DFS
    bool m_dfsViz[nMax] = {};

    // BFS
    int m_bfsDist[nMax] = {};
    queue<int> m_bfsQueue;

public:
    explicit Graf(int n = 0, int m = 0) : m_n(n), m_m(m) {}

    /*************** Algoritmi generali ***************/
    void DFS(int k) {
        m_dfsViz[k] = true;

        for (auto x: m_listAd[k]) {
            if (!m_dfsViz[x]) {
                DFS(x);
            }
        }
    }

    void BFS(int start) {
        m_bfsQueue.push(start);
        m_bfsDist[start] = 1;

        while (!m_bfsQueue.empty()) {
            int curr = m_bfsQueue.front();
            m_bfsQueue.pop();

            for (auto i: m_listAd[curr]) {
                if (m_bfsDist[i] == 0) {
                    m_bfsDist[i] = m_bfsDist[curr] + 1;
                    m_bfsQueue.push(i);
                }
            }
        }
    }

    const auto &getBFSDist() {
        return m_bfsDist;
    }

    /*************** Grafuri neorientate ***************/
    void neorientatCitesteListaAdiacenta(ifstream &in) {
        for (int i = 0; i < m_m; i++) {
            int x, y;
            in >> x >> y;
            m_listAd[x].push_back(y);
            m_listAd[y].push_back(x);
        }
    }

    int neorientatNrCompConexe() {
        int nrComp = 0;
        for (int i = 1; i <= m_n; i++) {
            if (!m_dfsViz[i]) {
                nrComp++;
                DFS(i);
            }
        }
        return nrComp;
    }

    /*************** Grafuri orientate ***************/
    void orientatCitesteListaAdiacenta(ifstream &in) {
        for (int i = 0; i < m_m; i++) {
            int x, y;
            in >> x >> y;
            m_listAd[x].push_back(y);
        }
    }
};

int main() {
    // Input rapid
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    // I/O
    ifstream in("bfs.in");
    ofstream out("bfs.out");

    int n, m, s;
    in >> n >> m >> s;
    in.close();

    Graf g(n, m);
    g.orientatCitesteListaAdiacenta(in);
    g.BFS(s);

    auto& bfsDist = g.getBFSDist();
    for (int i = 1; i <= n; i++) {
        out << ((bfsDist[i] == 0) ? -1 : bfsDist[i] - 1) << " ";
    }

    out.close();

    return 0;
}