Design Problems
94 Design LeetCode problems · Solve with AI-powered hints & step-by-step explanations.
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All Design problems
146 LRU Cache Medium155 Min Stack Medium173 Binary Search Tree Iterator Medium208 Implement Trie (Prefix Tree) Medium211 Design Add and Search Words Data Structure Medium225 Implement Stack using Queues Easy232 Implement Queue using Stacks Easy284 Peeking Iterator Medium295 Find Median from Data Stream Hard297 Serialize and Deserialize Binary Tree Hard303 Range Sum Query - Immutable Easy304 Range Sum Query 2D - Immutable Medium307 Range Sum Query - Mutable Medium341 Flatten Nested List Iterator Medium352 Data Stream as Disjoint Intervals Hard355 Design Twitter Medium380 Insert Delete GetRandom O(1) Medium381 Insert Delete GetRandom O(1) - Duplicates allowed Hard384 Shuffle an Array Medium432 All O`one Data Structure Hard449 Serialize and Deserialize BST Medium460 LFU Cache Hard535 Encode and Decode TinyURL Medium622 Design Circular Queue Medium641 Design Circular Deque Medium676 Implement Magic Dictionary Medium677 Map Sum Pairs Medium703 Kth Largest Element in a Stream Easy705 Design HashSet Easy706 Design HashMap Easy707 Design Linked List Medium715 Range Module Hard729 My Calendar I Medium731 My Calendar II Medium732 My Calendar III Hard745 Prefix and Suffix Search Hard855 Exam Room Medium895 Maximum Frequency Stack Hard900 RLE Iterator Medium901 Online Stock Span Medium911 Online Election Medium919 Complete Binary Tree Inserter Medium933 Number of Recent Calls Easy981 Time Based Key-Value Store Medium1032 Stream of Characters Hard1146 Snapshot Array Medium1157 Online Majority Element In Subarray Hard1172 Dinner Plate Stacks Hard1206 Design Skiplist Hard1261 Find Elements in a Contaminated Binary Tree Medium1286 Iterator for Combination Medium1348 Tweet Counts Per Frequency Medium1352 Product of the Last K Numbers Medium1357 Apply Discount Every n Orders Medium1381 Design a Stack With Increment Operation Medium1396 Design Underground System Medium1472 Design Browser History Medium1476 Subrectangle Queries Medium1483 Kth Ancestor of a Tree Node Hard1600 Throne Inheritance Medium1603 Design Parking System Easy1622 Fancy Sequence Hard1656 Design an Ordered Stream Easy1670 Design Front Middle Back Queue Medium1797 Design Authentication Manager Medium1825 Finding MK Average Hard1845 Seat Reservation Manager Medium1865 Finding Pairs With a Certain Sum Medium1912 Design Movie Rental System Hard1993 Operations on Tree Medium2013 Detect Squares Medium2034 Stock Price Fluctuation Medium2043 Simple Bank System Medium2069 Walking Robot Simulation II Medium2080 Range Frequency Queries Medium2102 Sequentially Ordinal Rank Tracker Hard2166 Design Bitset Medium2227 Encrypt and Decrypt Strings Hard2241 Design an ATM Machine Medium2276 Count Integers in Intervals Hard2286 Booking Concert Tickets in Groups Hard2296 Design a Text Editor Hard2336 Smallest Number in Infinite Set Medium2349 Design a Number Container System Medium2353 Design a Food Rating System Medium2424 Longest Uploaded Prefix Medium2502 Design Memory Allocator Medium2526 Find Consecutive Integers from a Data Stream Medium2642 Design Graph With Shortest Path Calculator Hard2671 Frequency Tracker Medium3242 Design Neighbor Sum Service Easy3408 Design Task Manager Medium3484 Design Spreadsheet Medium3508 Implement Router Medium