Platform for Object Oriented and Functional Programming Concepts

Leetcode Questions Index.

List of Leetcode questions. Few questions may not be from Leetcode but are equally important.

Tree

  1. Leetcode 94. Binary Tree Inorder Traversal (Recursive and Iterative)
  2. Leetcode 100. Same Tree or Identical binary trees.
  3. Leetcode 101. Symmetric Tree. Check whether the tree is a mirror of itself.
  4. Leetcode 144. Binary Tree Preorder Traversal (Recursive and Iterative)
  5. Leetcode 145. Binary Tree Postorder Traversal.
  6. Leetcode 173. Binary Search Tree Iterator.
  7. Leetcode 429. N-ary Tree Level Order Traversal.
  8. Leetcode 589. N-ary Tree Preorder Traversal using Recursion and Iteration.
  9. Leetcode 590. N-ary Tree Postorder Traversal using Recursion and Iteration.
  10. Binary Tree Preorder Iterator.
  11. Binary Tree Postorder Iterator.

String

  1. Leetcode 242. Valid Anagram.
  2. LeetCode 905. Sort Array By Parity–Moving Even Numbers to Left and Odd Numbers to Right.
  3. Find the first non-repeating character in a word.
  4. Count frequency of all characters in String.
  5. Count occurrences of a substring in input string.

Array

  1. LeetCode 905. Sort Array By Parity – Moving Even Numbers to Left and Odd Numbers to Right.
  2. Leetcode 922. Sort Array By Parity II. Moving Even elements to even index and odd elements to odd index.