Two Sum

Contains Duplicate

Product Except Self

The Sign of an Array

Arithmetic Progression

Maximum Sub-array

First Missing Possitive

Find Peak Element

Coin Change

Best Time to Buy and Sell Stocks

Tree Travarsal

Invert Binary Tree

Maximum Depth of Binary Tree

Linked List

Merge Two Linked Lists

Reverse Linked List

Longest Common Subsequence

Climbing Stairs

Trapping Rainwater

Hash Table

Linked List

Stack

Queue

Compare Two Strings with Backspace

Tree

Binary Search

Array

Binary Search Tree

Doubly Linked List

Graph

Set

Trie

Bubble Sort

Insertion Sort

Merge Sort

Quick Sort

Selection Sort

Shell Sort

Breadth First Travarsal

Depdth First Travarsal

Sorted Array to a Binary Search Tree

Reverse Only Letters

Reverse String II

Diameter of Binary Tree

Reverse Linked List II

Two pointers - Template 1

Two pointers - Template 2

Prefix Sum

Efficient string building

Linked list: fast and slow pointer

Find number of subarrays that fit an exact criteria

Monotonic increasing stack

Binary search: duplicate elements, left-most insertion point

Binary search: duplicate elements, right-most insertion point

Binary search: for greedy problems

Backtracking

Sliding Window