J. 7aseb El Triangle
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Consider a triangle configuration where points $$$B$$$, $$$C$$$, and $$$D$$$ lie on a straight line, and point $$$A$$$ is above this line forming the triangles $$$ABC$$$ and $$$ACD$$$.

Given:

  • $$$BC = CD$$$ (the segments are equal in length)
  • $$$\angle ABD = \alpha$$$ (the angle at vertex $$$B$$$ in triangle $$$ABD$$$)
  • $$$\angle ACD = \beta$$$ (the angle at vertex $$$C$$$ in triangle $$$ACD$$$)

Your task is to find the measure of $$$\angle ADC$$$ (the angle at vertex $$$D$$$ in triangle $$$ACD$$$).

Input

The only line contains two integers $$$\alpha$$$ and $$$\beta$$$ ($$$1 \le \alpha, \beta \lt 90$$$) — the measures of angles $$$\angle ABD$$$ and $$$\angle ACD$$$ in degrees.

It is guaranteed that the input corresponds to a valid geometric configuration.

Output

Print a single real number — the measure of angle $$$\angle ADC$$$ in degrees.

Your answer will be considered correct if its absolute or relative error does not exceed $$$10^{-6}$$$. Formally, let your answer be $$$a$$$, and the jury's answer be $$$b$$$. Your answer is considered correct if $$$\frac{|a - b|}{\max(1, |b|)} \le 10^{-6}$$$.

Examples
Input
2 6
Output
5.9422389569
Input
2 10
Output
3.3094179971
Note

Notice that the triangles need not be obtuse-angled.