public class Loop {
  /**
   * return original with the characters in reverse order
   */
  public String reverse (String original) {
    String reverse= "";
    int pos= original.length() - 1;
    
    // {reverse contains the characters of original from pos+1 to
    //  original.length()-1 reversed}
    while (pos != -1) {
      reverse= reverse + original.charAt(pos);
      pos= pos - 1;
    }
    // {reverse contains the characters of original from 0 to
    //  original.length()-1 reversed}
    return reverse;
  }
  
  public String reverse2 (String original) {
    String reverse= "";
    int pos= 0;
    
    // {reverse contains the characters of original from 0
    //  to pos-1 reversed}
    for (;pos != original.length();) {
      reverse = original.charAt(pos) + reverse;
      pos= pos + 1;
    }
    // {reverse contains the characters of original from 0
    //  to original.length() - 1 reversed}
   return reverse;
  }
}