Cod sursa(job #1435876)

Utilizator o_micBianca Costin o_mic Data 14 mai 2015 18:34:22
Problema BFS - Parcurgere in latime Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 0.8 kb
#include <fstream>
#include <iostream>
#include <vector>
#include <set>
#include <queue>
#define DN 100005
#define LL long long
using namespace std;

vector <int> gr[DN];
int viz[DN], lev[DN];

void bfs(int node){
  int x;
  queue <int> q;
  q.push(node);
  lev[node] = 0;
  while(!q.empty()){
    x = q.front();
    q.pop();
    viz[x] = 1;
    for(int i = 0; i < gr[x].size(); ++i){
      if(!viz[gr[x][i]]){
        lev[gr[x][i]] = lev[x] + 1;
        q.push(gr[x][i]);
      }
    }
  }
}

int main() {
  int n, m, s, x, y, res = 0;
  ifstream fin("bfs.in");
  ofstream fout("bfs.out");
  fin >> n >> m >> s;
  for(int i = 0; i < m; ++i){
    fin >> x >> y;
    gr[x].push_back(y);
  }
  for(int i = 1; i <= n; ++i)
    lev[i] = -1;
  bfs(s);
  for(int i = 1; i <= n; ++i){
    fout << lev[i] << " ";
  }
  return 0;
}