George has bought a pizza. George loves cheese. George thinks the pizza does not have enough cheese. George gets angry.

George’s pizza is round, and has a radius of $R$ cm. The outermost $C$ cm is crust, and does not have cheese. What percent of George’s pizza has cheese?

-----Input-----
The input consists of a single line with two space separated integers, $R$ and $C$.

-----Output-----
Output the percentage of the pizza that has cheese. Your answer must have an absolute or relative error of at most $10^{-6}$.

-----Limits-----
 - $1 \leq C \leq R \leq 100$

-----Examples-----
Sample Input:
1 1
Sample Output:
0.000000000

Difficulty: introductory

Starter code:

Solutions: