Dynamic Programming, Recursion, Competitive Programming, Leetcode, 3sum.
to the number. If I have an array of 4 elements, I can do 2 things. (1) I can just take the sum of the first 3 elements, or I can take the last element with any two elements from the first 3 elements. Optimal Substructure: The small example gives me a perspective. For each element, there are two