Dashboard Questions Topics Companies Sheets

Data Structures & Algorithms

Practice 3,374+ coding problems from top companies. Master DSA concepts and ace your interviews.

3,374

Problems

840

Easy

1762

Medium

772

Hard

Difficulty

All3374 Easy840 Medium1762 Hard772

Title	Solve	Difficulty	Companies	Topics
401. Binary Watch	Solve	Easy	Google	Backtracking Bit Manipulation
402. Remove K Digits	Solve	Medium	Adobe+6	Greedy Monotonic Stack+2
403. Frog Jump	Solve	Hard	Adobe+21	Array Dynamic Programming
404. Sum of Left Leaves	Solve	Easy	Adobe+6	Binary Tree Breadth-First Search+2
405. Convert a Number to Hexadecimal	Solve	Easy	Amazon+1	Bit Manipulation Math
406. Queue Reconstruction by Height	Solve	Medium	Facebook	Array Binary Indexed Tree+2
407. Trapping Rain Water II	Solve	Hard	Google	Array Breadth-First Search+2
408. Valid Word Abbreviation	Solve	Easy	Facebook+1	String Two Pointers
409. Longest Palindrome	Solve	Easy	Amazon	Greedy Hash Table+1
410. Split Array Largest Sum	Solve	Hard	Amazon+5	Array Binary Search+3
411. Minimum Unique Word Abbreviation	Solve	Hard	Google	Array Backtracking+2
412. Fizz Buzz	Solve	Easy	Apple+2	Math Simulation+1
413. Arithmetic Slices	Solve	Medium	Amazon+1	Array Dynamic Programming+1
414. Third Maximum Number	Solve	Easy	Amazon+2	Array Sorting
415. Add Strings	Solve	Easy	Amazon+7	Math Simulation+1
416. Partition Equal Subset Sum	Solve	Medium	Amazon+5	Array Dynamic Programming
417. Pacific Atlantic Water Flow	Solve	Medium	Amazon+3	Array Breadth-First Search+2
418. Sentence Screen Fitting	Solve	Medium	Google	Array Dynamic Programming+1
419. Battleships in a Board	Solve	Medium	Amazon+6	Array Depth-First Search+1
420. Strong Password Checker	Solve	Hard	Amazon+1	Greedy Heap (Priority Queue)+1
421. Maximum XOR of Two Numbers in an Array	Solve	Medium	Adobe+1	Array Bit Manipulation+2
422. Valid Word Square	Solve	Easy	Bloomberg+1	Array Matrix
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
425. Word Squares	Solve	Hard	Google	Array Backtracking+2
426. Convert Binary Search Tree to Sorted Doubly Linked List	Solve	Medium	Amazon+2	Binary Search Tree Binary Tree+5
427. Construct Quad Tree	Solve	Medium	Uber	Array Divide and Conquer+2
428. Serialize and Deserialize N-ary Tree	Solve	Hard	Amazon+7	Breadth-First Search Depth-First Search+2
429. N-ary Tree Level Order Traversal	Solve	Medium	Microsoft	Breadth-First Search Tree
430. Flatten a Multilevel Doubly Linked List	Solve	Medium	Amazon+3	Depth-First Search Doubly-Linked List+1
431. Encode N-ary Tree to Binary Tree	Solve	Hard	-	Binary Tree Breadth-First Search+3
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
434. Number of Segments in a String	Solve	Easy	Apple	String
435. Non-overlapping Intervals	Solve	Medium	Amazon+7	Array Dynamic Programming+2
436. Find Right Interval	Solve	Medium	Amazon+1	Array Binary Search+1
437. Path Sum III	Solve	Medium	DoorDash+3	Binary Tree Depth-First Search+1
438. Find All Anagrams in a String	Solve	Medium	Adobe+9	Hash Table Sliding Window+1
439. Ternary Expression Parser	Solve	Medium	Snapchat	Recursion Stack+1
440. K-th Smallest in Lexicographical Order	Solve	Hard	Bytedance+1	Trie
441. Arranging Coins	Solve	Easy	Adobe+5	Binary Search Math
442. Find All Duplicates in an Array	Solve	Medium	Adobe+4	Array Hash Table
443. String Compression	Solve	Medium	Amazon+8	String Two Pointers
444. Sequence Reconstruction	Solve	Medium	Google	Array Graph+1
445. Add Two Numbers II	Solve	Medium	Accenture+49	Linked List Math+1
446. Arithmetic Slices II - Subsequence	Solve	Hard	Adobe+3	Array Dynamic Programming
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
449. Serialize and Deserialize BST	Solve	Medium	Amazon+2	Binary Search Tree Binary Tree+5
450. Delete Node in a BST	Solve	Medium	Amazon+4	Binary Search Tree Binary Tree+1