DIY: Combination Sum

Solve the interview question "Combination Sum" in this lesson.

Problem statement

We are given a list of distinct integers named contenders. Our goal is to determine all possible ways to pick any or all of these integers such that they add to the value target. The same number may be picked for addition an unlimited number of times. Two arrangements of numbers that add to target are unique if they differ by at least one number. If two arrangements use the same set of numbers, they are still considered ...