FENCE1  Build a Fence
There is a wall in your backyard. It is so long that you can’t see its endpoints. You want to build a fence of length L such that the area enclosed between the wall and the fence is maximized. The fence can be of arbitrary shape, but only its two endpoints may touch the wall.
Input
The input consists of several test cases.
For every test case, there is only one integer L (1<=L<=100), indicating the length of the fence.
The input ends with L=0.
Output
For each test case, output one line containing the largest area. Your answer should be rounded to 2 digits after the decimal point.
Example
Input: 1 0 Output: 0.16
hide comments
sarthak_1998:
20190330 12:06:34
Taking the value of pi=3.142 and not as pi=3.14159 cost me two WAs 

rollicks_7:
20190208 07:00:00
What is the use of such fence? 

anant6025:
20190207 21:53:04
Just one basic geometry concept and than its too easy to implement! 

flyer2403:
20190101 18:59:19
In python 3 use:


sandeep48:
20181227 04:23:45
once you get the logic problem is super easy


gokul27:
20181218 14:49:25
AC in one go!!


identity_1x:
20180909 16:04:43
Dedicated to those struggling in java ,try using DecimalFormat for rounding to proper value , printf for setting the precision and use pi = 3.14159 . :) 

r210397:
20180626 20:54:40
why round is'nt working with python


Piotrek Nicowski:
20180508 15:34:17
I have an awful problem with this task in Java. For those who strugle with this task:


ash_maurya:
20180320 21:56:45
Implementation is easy. The only trick here is in precision. For C++, use fixed setprecision(2). 
Added by:  Fudan University Problem Setters 
Date:  20090523 
Time limit:  0.25s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: C99 ERL JSRHINO NODEJS PERL6 VB.NET 
Resource:  Fudan University Local Contest #1, practise session 