Cod sursa(job #2860831)

Utilizator pandurelPanduru Andrei pandurel Data 3 martie 2022 09:51:43
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.06 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>

#define NMax 100005

using namespace std;

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

int N, S, Distanta[NMax];
vector <int> vec[NMax];


void BFS(int nodStart)
{
    queue <int> Coada;

    Coada.push(nodStart);
    Distanta[nodStart] = 1;

    while( !Coada.empty() )
    {
        int nodCurent = Coada.front();
        Coada.pop();

        for(unsigned int i = 0; i < vec[nodCurent].size(); ++ i)
            if(Distanta[vec[nodCurent][i]] == 0)
            {
                Distanta[vec[nodCurent][i]] = Distanta[nodCurent] + 1;
                Coada.push(vec[nodCurent][i]);
            }
    }
}

int main()
{
    int M, x, y;

    fin >> N >> M >> S;
    for(int i = 1; i <= M; ++ i)
    {
        fin >> x >> y;
        vec[x].push_back(y);
    }

    BFS(S);

    for(int i = 1; i <= N; ++ i)
    {
        if(Distanta[i] != 0)
            fout << Distanta[i] - 1 << ' ';
        else fout << -1 << ' ';
    }

    return 0;
}