Dashboard Questions Topics Companies Sheets

Hash Table

Topic

645 coding problems covering Hash Table concepts. Master this topic and improve your problem-solving skills.

645

Problems

158

Easy

383

Medium

104

Hard

Difficulty

All645 Easy158 Medium383 Hard104

Title	Solve	Difficulty	Companies	Topics
311. Sparse Matrix Multiplication	Solve	Medium	Amazon+3	Array Hash Table+1
314. Binary Tree Vertical Order Traversal	Solve	Medium	Amazon+3	Binary Tree Breadth-First Search+4
325. Maximum Size Subarray Sum Equals k	Solve	Medium	Amazon+1	Array Hash Table+1
336. Palindrome Pairs	Solve	Hard	Airbnb+5	Array Hash Table+2
340. Longest Substring with At Most K Distinct Characters	Solve	Medium	Amazon+1	Hash Table Sliding Window+1
347. Top K Frequent Elements	Solve	Medium	Adobe+9	Array Bucket Sort+6
348. Design Tic-Tac-Toe	Solve	Medium	Adobe+4	Array Design+3
349. Intersection of Two Arrays	Solve	Easy	Adobe+7	Array Binary Search+3
350. Intersection of Two Arrays II	Solve	Easy	Adobe+4	Array Binary Search+3
353. Design Snake Game	Solve	Medium	Amazon+6	Array Design+3
355. Design Twitter	Solve	Medium	Amazon+2	Design Hash Table+2
356. Line Reflection	Solve	Medium	Yandex	Array Hash Table+1
358. Rearrange String k Distance Apart	Solve	Hard	Google+3	Counting Greedy+4
359. Logger Rate Limiter	Solve	Easy	Amazon+5	Data Stream Design+1
379. Design Phone Directory	Solve	Medium	Amazon+1	Array Design+3
380. Insert Delete GetRandom O(1)	Solve	Medium	Affirm+8	Array Design+3
381. Insert Delete GetRandom O(1) - Duplicates allowed	Solve	Hard	Affirm+2	Array Design+3
383. Ransom Note	Solve	Easy	Adobe+3	Counting Hash Table+1
387. First Unique Character in a String	Solve	Easy	Amazon+8	Counting Hash Table+2
389. Find the Difference	Solve	Easy	Adobe+4	Bit Manipulation Hash Table+2
395. Longest Substring with At Least K Repeating Characters	Solve	Medium	Amazon+1	Divide and Conquer Hash Table+2
398. Random Pick Index	Solve	Medium	Amazon+2	Hash Table Math+2
409. Longest Palindrome	Solve	Easy	Amazon	Greedy Hash Table+1
421. Maximum XOR of Two Numbers in an Array	Solve	Medium	Adobe+1	Array Bit Manipulation+2
423. Reconstruct Original Digits from English	Solve	Medium	JPMorgan	Hash Table Math+1
424. Longest Repeating Character Replacement	Solve	Medium	Adobe+3	Hash Table Sliding Window+1
432. All O`one Data Structure	Solve	Hard	Amazon+2	Design Doubly-Linked List+2
433. Minimum Genetic Mutation	Solve	Medium	Amazon+4	Breadth-First Search Hash Table+1
438. Find All Anagrams in a String	Solve	Medium	Adobe+9	Hash Table Sliding Window+1
442. Find All Duplicates in an Array	Solve	Medium	Adobe+4	Array Hash Table
447. Number of Boomerangs	Solve	Medium	Google	Array Hash Table+1
448. Find All Numbers Disappeared in an Array	Solve	Easy	Amazon+3	Array Hash Table
451. Sort Characters By Frequency	Solve	Medium	Amazon+4	Bucket Sort Counting+4
454. 4Sum II	Solve	Medium	Adobe+3	Array Hash Table
457. Circular Array Loop	Solve	Medium	Goldman Sachs	Array Hash Table+1
460. LFU Cache	Solve	Hard	Amazon+9	Design Doubly-Linked List+2
480. Sliding Window Median	Solve	Hard	Facebook+3	Array Hash Table+2
491. Non-decreasing Subsequences	Solve	Medium	Amazon+1	Array Backtracking+2
496. Next Greater Element I	Solve	Easy	Adobe+9	Array Hash Table+2
500. Keyboard Row	Solve	Easy	Mathworks	Array Hash Table+1
508. Most Frequent Subtree Sum	Solve	Medium	Apple	Binary Tree Depth-First Search+2
519. Random Flip Matrix	Solve	Medium	Google	Hash Table Math+2
522. Longest Uncommon Subsequence II	Solve	Medium	Apple	Array Hash Table+3
523. Continuous Subarray Sum	Solve	Medium	Amazon+6	Array Hash Table+2
525. Contiguous Array	Solve	Medium	Amazon+3	Array Hash Table+1
531. Lonely Pixel I	Solve	Medium	Google+2	Array Hash Table+1
532. K-diff Pairs in an Array	Solve	Medium	Adobe+7	Array Binary Search+3
533. Lonely Pixel II	Solve	Medium	Google	Array Hash Table+1
535. Encode and Decode TinyURL	Solve	Medium	Amazon+2	Design Hash Function+2
548. Split Array with Equal Sum	Solve	Hard	Facebook	Array Hash Table+1