private String calc(String input) {
	  //Person 3 put your implementation here
	  char[] letters = input.toCharArray();
	  char[] reversedChar = new char[letters.length];
		  
	  for(int i = 0; i < letters.length; i++){
	    reversedChar[i] = letters[(letters.length - 1) - i];
	  }
	  String reversedStr = new String(reversedChar);
	  return reversedStr;
	}