/*
 * File: FindPrimes.java
 * ---------------------
 * This program finds all prime numbers between the constants
 * LOWER_BOUND and UPPER_BOUND.
 *
 * Author: CS1MD3, Oct. 2008
 */

import acm.program.*;

public class FindPrimes extends ConsoleProgram {

   public void run() {
      for (int i = LOWER_BOUND; i <= UPPER_BOUND; i++) {
         if (isPrime(i)) println(i);
      }
   }

/* Returns true if *n* is a prime number */
   private boolean isPrime(int n) {
      if (n < 2) return false;
      /* if n is even, only 2 is a prime */
      if (n % 2 == 0) return (n == 2);
      /* when n >2 and odd */
      int limit = (int) Math.round(Math.sqrt(n));
      for (int i = 3; i <= limit; i += 2) {
         if (n % i == 0) return false;
      }
      return true;
   }

/* Lower and upper bound constants */
   private static final int LOWER_BOUND = 1;
   private static final int UPPER_BOUND = 1000;

}