216. Combination Sum III

Practice Combination Sum III for free on NudgeCode: Medium, Backtracking pattern. Write it in Python or JavaScript, run the tests in your browser, and ask for a hint when you are stuck.

Pick k different numbers from 1 to 9 so that they add up to n. Return every such combination; each number is used at most once per combination, and no combination may appear twice. The combinations, and the numbers inside each, can be in any order. Return [] if there is none.

Example

k = 3, n = 9  ->  [[1,2,6],[1,3,5],[2,3,4]]

Constraints