##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
Generate C(n,k)
Given two integers and , return all possible combinations of numbers chosen from the range . For example, if and , you return .
This is the classic combinations problem. You learned counts how many combinations exist. Now you will generate them all.
The key constraint: order does not matter. and are the same combination. You need to avoid duplicates.
