Solution: Combination Sum

Explore a dynamic programming solution to generate all unique combinations of numbers summing to a target. Understand the problem's optimal substructure and overlapping subproblems properties. Learn to build and use a DP table that avoids redundant computation, improving efficiency for combination sum problems in C++. This lesson helps you implement and analyze this approach with focus on time and space tradeoffs.

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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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