Cod sursa(job #632687)

Utilizator sory1806Sandu Sorina-Gabriela sory1806 Data 12 noiembrie 2011 00:34:59
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include <cstdio>
#include <queue>
#include <vector>

#define MAX_N 100010

using namespace std;

vector <int> ad[MAX_N];
int dist[MAX_N], n, m, s;

void read() {
  int x, y;

  scanf("%d%d%d", &n, &m, &s);

  for(int i = 0; i < m; i ++) {
    scanf("%d%d", &x, &y);
    ad[x].push_back(y);
  }
}

void solve() {
  queue <int> q;
  int x;

  for(int i = 1; i <= n; i ++)
    dist[i] = -1;

  q.push(s);
  dist[s] = 0;

  while(!q.empty()) {
    x = q.front();
    for(int i = 0; i < ad[x].size(); i ++)
      if(dist[ad[x][i]] == -1) {
	q.push(ad[x][i]);
	dist[ad[x][i]] = dist[x] + 1;
      }

    q.pop();
  }
}

void write() {
  for(int i = 1; i <= n; i ++)
    printf("%d ", dist[i]);
  printf("\n");
}
int main() {

  freopen("bfs.in", "r", stdin);
  freopen("bfs.out", "w", stdout);

  read();
  solve();
  write();

  return 0;
}