Largest inscribed rectangle

Output the maximum area of a rectangle that can be inscribed into a circle of radius r. Rectangle's shorter side should not be longer than b.

Input

First line contains the number of test cases t (1 ≤ t ≤ 1000). Next t lines each contain two integers r and b (1 ≤ r, b ≤ 10000).

Output

For each test case print on a separate line the maximum area of a rectangle with a maximum shorter side b that can be inscribed into a circle of radius r. Your answer should be rounded to three digits after the decimal point (see sample output).

Examples