Description

An elephant is thirsty and needs to drink 20 liters of water to quench its thirst. However, there is only a small cylindrical bucket with a depth of h centimeters and a base radius of r centimeters (h and r are both integers).
The question is: What is the minimum number of buckets of water the elephant must drink to quench its thirst?

Input Format

The input consists of a single line containing two integers separated by a space, representing the depth h and the base radius r of the small bucket, both in centimeters.

Output Format

Output a single line containing an integer, representing the minimum number of buckets the elephant must drink.

23 11

3

Hint

1 liter = 1000 cubic centimeters.