IITKWPCN  Playing With Balls
There are W white balls and B black balls in a bag. A magician is performing tricks by drawing balls from the bag.
In each step, the magician randomly removes any two balls from the bag. If the drawn balls are of the same color, he will put one white ball in the bag, otherwise he will put a black ball in it. The two drawn balls from the bag from the ball are discarded.
He keeps on doing the above tricks until there is only one ball remaining in the bag.
Given W and B, you have to determine the probability that the color of last ball remaining in the bag is black. You should print the answer with accuracy of upto 6 decimal digits.
Input
T : no of test cases (1 <= T <= 10^4)
For every test case W and B are given (0 <= W <= 10^8 and 0 <= B <= 10^8 and W + B != 0)
Output
For each test case, output the probability as stated in the problem statement.
Example
Input: 2 1 1 1 2 Output: 1.000000 0.000000
hide comments
Vipul Pandey:
20140105 21:57:12
easy if you get it. Otherwise a good problem of probability. 

tbos:
20140104 15:03:13
AC in a Go


ritz:
20140104 14:04:40
nice problem statement :) (Y) 

ABHISHEK004:
20140102 20:51:00
simple....


RG:
20131230 06:58:54
Yeah its really too simple... No need for programming Simple probability.. :) 

Ankit Kumar:
20131224 12:38:35
Hint : It's just TOO simple ;)


Anubhav Balodhi :
20131223 19:48:03
Good Q on Probability theory... 

Raman Shukla:
20130824 12:38:24
Nice one... My 150th Classical on spoj... 
Added by:  praveen123 
Date:  20130806 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: ASM64 
Resource:  IITK ACA CSE online judge 