Guess The Number

Guess the number is a simple game where you need to guess a random number.
Each time you guess the random number, you will get a bonus number of bank points.

At the begining you have 1000 bank points you can use to guess the numbers.
You have to bet a number of points from the bank each time until you will get the right answer. The random number changes after each bet. If the random number generated in current round was in the interval (1 , "your bet"), the interval wil shrink to (1 , "your bet") and the bet points returns to your bank, if not you will loose the bet points.
Each guess costs a number of points.