Leetcode should be about practice, not memorizing. Know the basics. Breadth first and depth first. Know different data structures; binary tree, arrays, linked l

Leetcode should be about practice, not memorizing. Know the basics. Breadth first and depth first. Know different data structures; binary tree, arrays, linked lists, dictionaries, hashes, sets. Know your sorts. Have an understanding of big o. Just knowing the basics will get you most of the way there.