Generating all the subsets or permutations using stl

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1

I have 3 question -

  1. How to generate all the subsets?
  2. How to generate all the subsets of a given length?
  3. How to generate all the permutations?

How to do this using stl?

2

@mathecodician Here is the code IdeOne - All Subsets to generate all possible subsets of a given array of numbers.

For subsets of a given size , see this code IdeOne - Subsets of a given size : . It is taken from second answer here : http://stackoverflow.com/questions/4555565/generate-all-subsets-of-size-k-from-a-set . Here’s another link on generating subsets of a given length GeeksForGeeks - All Combinations of R elements from Array of size N

For permutations, I don’t think you will need STL library as shown in the example here (Official Website) . You just sort the given array and use the next_permutation function iteratively to generate all possible subsets. And if want to generate all possible permutations of a given string, you should see the tutorial here : GeeksforGeeks - Print all permutations of a given String

By the way, I found many answers on the Internet for subsets which used Bit Manipulation but I don’t understand that much so I avoided it. However if you are used to with bits, then you may see the topmost links on a google search! (Example : GeeksforGeeks - generating Power Set and All Subsets using Bit Manipulation )

3

Is there an STL way to do the subsets thing?

4

Tbh @mathecodician, even I don’t how to do the subset thing using STL.
I don’t think there’s any such function in STL which would help in that.

5

In python there is the itertools library though

6

Yea. Generating subsets and permutations using itertools merely reduces to one line or so in Python. Surely a lifesaver! :smiley: