PIE - Pie


My birthday is coming up and traditionally I'm serving pie. Not just one pie, no, I have a number N of them, of various tastes and of various sizes. F of my friends are coming to my party and each of them gets a piece of pie. This should be one piece of one pie, not several small pieces since that looks messy. This piece can be one whole pie though.

My friends are very annoying and if one of them gets a bigger piece than the others, they start complaining. Therefore all of them should get equally sized (but not necessarily equally shaped) pieces, even if this leads to some pie getting spoiled (which is better than spoiling the party). Of course, I want a piece of pie for myself too, and that piece should also be of the same size.

What is the largest possible piece size all of us can get? All the pies are cylindrical in shape and they all have the same height 1, but the radii of the pies can be different.

Input

One line with a positive integer: the number of test cases. Then for each test case:

  • One line with two integers N and F with 1 ≤ N, F ≤ 10000: the number of pies and the number of friends.
  • One line with N integers ri with 1 ≤ ri ≤ 10000: the radii of the pies.

Output

For each test case, output one line with the largest possible volume V such that me and my friends can all get a pie piece of size V. The answer should be given as a floating point number with an absolute error of at most 10-3.

Example

Input:
3
3 3
4 3 3
1 24
5
10 5
1 4 2 3 4 5 6 5 4 2

Output:
25.1327
3.1416
50.2655

hide comments
kshubham02: 2017-09-25 13:00:15

Something is seriously flawed with float in c++. Got 9 TLE using float, changed it to double, immediately AC (well, after 4 attempts at precision).

lord_poseidon: 2017-09-23 14:16:02

Use precise value of pi

jatin03: 2017-08-19 14:47:52

Thanks @aditya23 It really means a alot :)

aditya23: 2017-08-19 14:42:56

Doubles are not floats, so do not compare them !! (Mind It)

Last edit: 2017-08-19 14:46:07
code_aim: 2017-06-10 11:02:31

avoid using cout, instead use printf.

roukaya_zaki: 2017-02-08 15:49:09

must I calculate the volume of the pie before I began to distribute them?!

ayush5148: 2016-08-26 23:12:23

float costed me 2 WA, use double in c/c++...

Last edit: 2016-08-26 23:14:33
suraj_: 2016-08-22 12:37:28

AC in one go.....

adichd123: 2016-08-15 12:36:42

use printf please...cout gives WA!

Akshay Damle: 2016-04-21 16:17:55

Nice question! You don't need long double - double is fine. Just use a precise value of PI.


Added by:overwise
Date:2007-10-02
Time limit:0.751s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:ACM ICPC NWERC 2006