CF441E Valera and Number

Valera is a coder. Recently he wrote a funny program. The pseudo code for this program is given below: ```plain //input: integers x, k, p a = x; for(step = 1; step

The first line of the input contains three integers $ x,k,p $ ( $ 1

Print the required expected value. Your answer will be considered correct if the absolute or relative error doesn't exceed $ 10^{-6} $ .

If the concept of expected value is new to you, you can read about it by the link: http://en.wikipedia.org/wiki/Expected\_value