public class Test {


  public static void main(String[] args) {
    final int LIMIT = 100; // how many bulbs
    boolean[] bulbs = new boolean[LIMIT]; // the bulbs
    // switch them all on
    for (int i = 0; i < LIMIT; i++) {
      bulbs[i] = true;
    }
    //the different men
    for (int man = 2; man < LIMIT + 1; man++) {
      for (int position = man; position < LIMIT; position += man) {
        bulbs[position] = !bulbs[position]; // flip bulb true <--> false
      }
    }
    //how many on now?
    int count = 0;
    for (int i = 0; i < LIMIT; i++) {
      if (bulbs[i]) {
        count++;
      }
    }
    System.out.println(count);

  }

}