Problems
Circle
Circle
\includegraphics{https://static.e-olymp.com/content/96/96ed6508f858eaedff187caa2ce52166d75238c9.jpg}
How many points with integer coordinates are in a circle with radius $r$? The point on a circle is considered to be in a circle. The center of the circle has integer coordinates.
\InputFile
The integer radius of a circle $r~(r \le 15000)$.
\OutputFile
Print the required number of points.
Input example #1
2
Output example #1
13