Leetcode

New problems

564. Find the Closest Palindrome

Concepts: Math, String

Revisited problems

1405. Longest Happy String

Concepts: Heap

670. Maximum Swap

Concepts: Math

994. Rotting Oranges

Concepts: Queue, BFS

131. Palindrome Partitioning

Concepts: Dynamic Programming

Other ways to solve this problem, but DP is my favorite way.

348. Design Tic-Tac-Toe

Concepts: Array, Hash Table