SCPC11G  Indomie
During recession, Amjad needs to queue for SembakoPlus. Sembako, as we all know, stands for “Sembilan Bahan Pokok” which consists of 9 kinds of item: Rice, Sugar, Cookingoil, Meat, Egg, Milk, Corn, Kerosene and Iodized Salt. SembakoPlus consists of Sembako and one more item: Indomie! Amjad’s favorite of all time!! (therefore, no wonder why he could stand for this long queue).
Each person in the queue is allowed to pick only one item. No need to ask, Amjad wants only Indomie. Unfortunately, they are running out of SembakoPlus stock and currently there are three kinds of item left: Rice, Sugar and Indomie. As he could see from afar, he is quite sure that Rice and Sugar will be enough for everybody.
Given the number of remaining Indomie and the number of people queuing in front of Amjad, your task is to count the probability that he will get his Indomie. Amjad can’t do programming right now as he is very nervous so he can’t think logically. He needs your help!
Input
There will be multiple test cases for this problem. Each test case contains two integers N (1 ≤ N ≤ 50) and S (0 ≤ S ≤ 50), where N is the number of people queuing in front of Amjad and S is the remaining number of Indomie.
For each case, print in a single line the probability in percentage that he will get his Indomie with 5 digits precision (he’s being paranoid)
Example
Input: 2 1 3 2 4 0 4 1 10 10 14 9 30 14 Output: 50.00000 76.92308 0.00000 33.33333 99.99831 98.65515 95.16071
hide comments
hodobox:
20170507 13:42:05
Yeah, the probabilities of each sequence don't follow a probability tree. You are just supposed to count (number of possible sequences where at least 1 Indomie is not eaten)/(number of all possible sequences) Last edit: 20170507 13:42:48 

zicowa:
20140714 17:17:34
A simple optimisation will definately work :P :D O((nk)*k) passed AC 

Hussain Kara Fallah:
20120820 01:31:05
You should use BIG INT .... Be careful ! 

Bharath Reddy:
20120711 09:44:20
@fitcat and Tywan: You can't have the combination Indomie, Indomie for the first test case. So the probability is only 0.5 

berney:
20120326 08:50:33
my code runs fine in ideone(in java6)...


Devil D:
20111228 08:45:03
what is the answer for 20 19 ?


fitcat:
20111126 09:27:47
The example output is incorrect. For the 1st sample test case, the correct answer should be 2/3*2/3 = 4/9 = 44.44444 as Tywan pointed it out. 

Tywan:
20111027 08:13:58
I've solved the problem but still believe the right answer should be


Lukmanul Hakim:
20111024 01:46:27
What? Indomie from Syria? :O 

Ayan Ghatak:
20111021 13:59:07
how long do i scan??till eof?? 
Added by:  Ali Arous 
Date:  20111019 
Time limit:  0.903s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: ASM64 
Resource:  Syrian Collegiate Programming Contest 2011 