// Assignment 13 solutions

abstract public class Basic {

  public static int sum_of_squares (int x, int y) {
    return (x * x) + (y * y);
  } // end sum_of_squares

  public static int fact (int n) {
    if (n == 0) 
      return 1;
    else
      return n * fact(n - 1);
  } // end fact

  public static int fib (int n) {
    if (n <= 1)
      return n;
    else
      return fib(n - 1) + fib(n - 2);
  } // end fib

  // A fun iterative solution.
  public static int num_reverse (int n) {
    int from = n;
    int to = 0;

    while (0 < from) {
      to = (to * 10) + (from % 10);
      from = from / 10;
    }
    return to;
  } // end num_reverse

} // end class Basic