题目描述
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
输入格式
见题面
输出格式
见题面
样例输入
1 1
样例输出
0.000000000