Cod sursa(job #2647343)

Utilizator MihaiG09Gheorghe Mihai MihaiG09 Data 3 septembrie 2020 23:51:24
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.22 kb
#include <iostream>
#include <queue>
#include <vector>
#include <algorithm>
#include <cmath>
#include <fstream>

using namespace std;

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

const int NMax = 100001;
queue <int> coada;
vector <int> v[NMax];
int viz[NMax], c[NMax];
int n, m, s;

void citire()
{
    fin >> n >> m >> s;
    for(int i = 1; i <= m; i++)
    {
        int x, y;
        fin >> x >> y;
        if(x != y)
        {
            v[x].push_back(y);

        }

    }
}

void AfisareGraph()
{
    for(int i = 1; i <= n; i++)
    {
        fout << i << ": ";
        for(auto j : v[i])
            fout << j << " ";
        fout << endl;
    }
}

void BFS(int a)
{
    coada.push(a);
    viz[a] = 1;
    for(int i = 1; i <= n; i++)
        c[i] = -1;
    c[a] = 0;
    while(coada.empty() == false)
    {
        int d = coada.front();
        coada.pop();
        for(auto j : v[d])
            if(viz[j] == 0)
        {
            viz[j] = 1;
            coada.push(j);
            c[j] = c[d] + 1;
        }

    }
}

int main()
{
    citire();
    //AfisareGraph();
    BFS(s);
    for(int i = 1; i <= n; i++)
        fout << c[i] << " ";
    return 0;
}