Cod sursa(job #1156350)

Utilizator sergiunascaSergiu Nasca sergiunasca Data 27 martie 2014 16:28:23
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.01 kb
#include <fstream>
#include <vector>
#include <queue>
#include <bitset>
#define NMax 100002
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
int n,m,x,y,start;
std::vector<int> G[NMax],Numar;
std::bitset<NMax> viz;
std::queue<int> coada;
void bfs(int x0)
{
    coada.push(x0);
    viz[x0] = true;
    while(coada.empty()==0)
    {
        int nod = coada.front();
        coada.pop();
        for(int i=0;i<G[nod].size();++i)
        {
            if(!viz[G[nod][i]])
            {
                viz[G[nod][i]] = true;
                Numar[G[nod][i]] = Numar[nod] + 1;
                coada.push(G[nod][i]);
            }
        }
    }
}
int main()
{
    fin>>n>>m>>start;
    Numar.resize(n+10);
    for(int i=1;i<=m;++i)
    {
        fin>>x>>y;
        G[x].push_back(y);
    }
    bfs(start);
    for(int i=1;i<=n;++i)
    {
        if(i==start)fout<<"0 ";
        else if(Numar[i]==0)fout<<"-1 ";
        else fout<<Numar[i]<<" ";
    }
    return 0;
}