Cod sursa(job #2081403)

Utilizator filip.mihalutMihalut Filip filip.mihalut Data 4 decembrie 2017 18:10:59
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.88 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#define dim 100004

using namespace std;

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

vector < int > v[dim];
int vizitat[dim] , n , m , S,x , y , next_x;

void read()
{
    f >> n >> m >> S;

    for(int i = 1;i <= m;i++)
    {
        f >> x >> y;
        v[x].push_back(y);
    }
}

void bfs()
{
    queue < int > Q;
    Q.push(S);
    vizitat[S] = 1;

    while(not Q.empty())
    {
        x = Q.front();
        Q.pop();
        int l = v[x].size();

        for(int i = 0;i < l;i++)
        {
            next_x = v[x][i];

            if(not vizitat[next_x])
                vizitat[next_x] = vizitat[x] + 1, Q.push(next_x);
        }
    }
}

int main()
{
    read();
    bfs();

    for(int i = 1;i <= n;i++)
        g << vizitat[i] - 1 << " ";
    return 0;
}