1 – Variable
- Reverse Integer
- Fizz Buzz
2 – Loops, Function & OOP
if, for, while
- Palindrome Number
- Swap Two Integers in Array
3 – Linear Data Structure I
List, String
- String to Integer
- Remove Duplicates from Sorted Array
- Remove Element
- Reverse Words in a String
- Valid Palindrome
4 – Linear Data Structure II
Linked list, Stack, Queue
- Implement Stack using Queues
- Remove Linked List Elements
- Valid Parentheses
- Remove Nth Node From End of List
- Merge Two Sorted Lists
- Reverse Linked List
- Implement Queue using Stacks
5 – Binary Tree & Depth First Traversal
- Validate Binary Search Tree
- Binary Tree Zigzag Level Order Traversal
6 – Breadth First Traversal & BST
- Binary Tree Zigzag Level Order Traversal
- Validate Binary Search Tree
7 – Set, Dictionary & Divide and Conquer
- Same Tree
- Two Sum
8 – Sort Algorithm
- Merge Two Sorted Arrays
- Subarray Sum Closest