Solution: Combination Sum

Explore solving the Combination Sum problem using dynamic programming. Understand how to build a dp table to generate unique combinations from an array of integers that sum to a given target, analyze time and space complexity, and optimize naive recursive methods.

We'll cover the following...

Statement
Solution
- Naive approach
- Optimized approach using dynamic programming

Statement

Given an array of distinct integers, nums, and an integer, target, return a list of all unique combinations of nums where the chosen numbers sum up to the target. The combinations may be returned in any order.

An integer from nums may be chosen an unlimited number of times. Two combinations are unique if the frequency of at least one of the chosen integers is different.

Constraints:

$1 \leq$ nums.length $\leq 30$
$2 \leq$ nums[i] $\leq 40$
$1 \leq$ target $\leq 40$

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