Exercise: Reverse the number guessing game

In this version you think about a number between 1-200 and press the "start" button. Then the computer guesses and you have to tell it if the guessed number is the one you thought about, or if it is smaller or larger than what you thought about. For this you might need to add 3 new buttons. If your answer was "smaller" or "bigger", the computer guesses again. How many guesses does your program need?