Cod sursa(job #2796356)

Utilizator 6kmeleon6Luca Cordus 6kmeleon6 Data 7 noiembrie 2021 22:33:49
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.37 kb
#include <bits/stdc++.h>

using namespace std;

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

class Graf
{
    int nr_N, nr_M, S;
    vector<int> adiac[100001];

public:

    /// Constructori
    Graf() : nr_N(0), nr_M(0) {}
    Graf(int N, int M) : nr_N(N), nr_M(M) {}

    void citire();
    void BFS();
};

void Graf::citire()
{
    in >> nr_N >> nr_M >> S;
    for (int i = 0; i < nr_M; i++)
    {
        int x, y;
        in >> x >> y;
        adiac[x].push_back(y);
    }
}

void Graf::BFS()
{
    queue <int> coada;
    int nod;
    int vizitat[100001] = {};
    vizitat[S] = 1;
    coada.push(S);
    int cost[100001] = {};
    cost[S] = 0;///Costul la nodul de start este 0

    while(coada.size() > 0) ///Cat timp inca mai am noduri in graf
    {
        nod = coada.front();

        for(int j = 0; j < adiac[nod].size(); j++)
        {

                if(vizitat[adiac[nod][j]] == 0)
                {
                    coada.push(adiac[nod][j]);
                    cost[adiac[nod][j]] = cost[nod] + 1;
                    vizitat[adiac[nod][j]]++;
                }

        }
        coada.pop();
    }

    for(int i = 1; i <= nr_N; i++)
        {
            if(vizitat[i] == 0) out << "-1 "; else out << cost[i] << " ";
        }
}

int main()
{
    Graf G;
    G.citire();
    G.BFS();
    return 0;
}