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a question in building recursion..

alex lotel
Ranch Hand

Joined: Feb 01, 2008
Posts: 191
i got this question that i dond have any clue
what they want from me
it says:

build a method that takes two integer numbers
the method prints out all the subgroops
if the size of k
for example

i cant find out was it the legality in these groops
because it meeses 22 31
Anand Hariharan

Joined: Aug 22, 2006
Posts: 272

Welcome to the forum.

It appears that they are looking for the number of ways you can select 'k' elements from 'n' elements (without considering arrangement). This is called COMBINATION (if arrangment is considered, it is called PERMUTATION).

In your example, '22' is disallowed because once '2' is picked from {1,2,3,4}, it cannot be selected again. Since we disregard arrangement, '31' is the same as '13', and '13' is a part of your "subgroup".

Am not sure if "subgroup" is a right terminology here, but I guess it depends upon the curriculum.

- Anand

"Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away." -- Antoine de Saint-Exupery
I agree. Here's the link:
subject: a question in building recursion..
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