All problems that are about designing a system.
LFU cache - January 29, 2023
Design a leaderboard - December 28, 2022
Prefix and suffix search - December 27, 2022
Moving average from data stream - December 13, 2022
Design hit counter - December 9, 2022
Range frequency queries - December 8, 2022
Design tic tac toe - December 7, 2022
Encode and decode strings - December 6, 2022
Implement trie II (prefix tree) - December 4, 2022
Unique word abbreviation - November 30, 2022
Design hashset - November 28, 2022
Design phone directory - November 28, 2022
Random pick index - November 22, 2022
Shuffle an array - November 22, 2022
design linked list - November 21, 2022
Maximum frequency stack - November 13, 2022
Design an ordered stream - November 6, 2022
Encode and decode tinyurl - November 4, 2022
Longest uploaded prefix - October 26, 2022
Serialize and deserialize bst - October 25, 2022
Number of recent calls - October 11, 2022
Design front middle back queue - September 29, 2022
Product of the last k numbers - September 28, 2022
Flatten nested list iterator - September 27, 2022
Design circular deque - September 27, 2022
Iterator for combination - September 17, 2022
Finding pairs with a certain sum - September 16, 2022
Design an atm machine - September 16, 2022
Range sum query immutable - September 13, 2022
Design a food rating system - September 9, 2022
Peeking iterator - September 9, 2022
Implement magic dictionary - September 6, 2022
Design a stack with increment operation - September 6, 2022
Design underground system - September 3, 2022
Design parking system - August 19, 2022
Design circular queue - August 13, 2022
Find median from data stream - August 7, 2022
Design twitter - August 6, 2022
Serialize and deserialize binary tree - August 6, 2022
LRU cache - August 5, 2022
Implement queue using stacks - July 24, 2022
Design add and search words data structure - July 23, 2022
Time based key value store - July 23, 2022
Implement trie prefix tree - July 21, 2022
Implement stack using queues - July 21, 2022
Min stack - July 19, 2022