class Exercise5
{
  // overwrites every occurrence of 'x' in 'a' by 'y'
  // returns true iff some element was overwritten
  public static boolean overwrite(int[] a, int x, int y)
  {
    boolean result = false;
    int n = a.length;
    int i = 0;
    while (i < n)
    {
      if (a[i] == x)
      {
        a[i] = y;
        result = true;
      }
      i = i+1;
    }
    return result;
  }
}