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
616. Add Bold Tag in String	Solve	Medium	Facebook	Array Hash Table+3
621. Task Scheduler	Solve	Medium	Amazon+4	Array Counting+4
622. Design Circular Queue	Solve	Medium	Airbnb+5	Array Design+2
623. Add One Row to Tree	Solve	Medium	Amazon+2	Binary Tree Breadth-First Search+2
624. Maximum Distance in Arrays	Solve	Medium	Yahoo	Array Greedy
625. Minimum Factorization	Solve	Medium	Tencent	Greedy Math
626. Exchange Seats	Solve	Medium	Amazon+3	Database
633. Sum of Square Numbers	Solve	Medium	Amazon+1	Binary Search Math+1
634. Find the Derangement of An Array	Solve	Medium	Amazon+1	Dynamic Programming Math
635. Design Log Storage System	Solve	Medium	Twitter	Design Hash Table+2
636. Exclusive Time of Functions	Solve	Medium	DoorDash+4	Array Stack
638. Shopping Offers	Solve	Medium	Amazon+3	Array Backtracking+4
640. Solve the Equation	Solve	Medium	Amazon+1	Math Simulation+1
641. Design Circular Deque	Solve	Medium	-	Array Design+2
646. Maximum Length of Pair Chain	Solve	Medium	Amazon+12	Array Dynamic Programming+2
647. Palindromic Substrings	Solve	Medium	Expedia+2	Dynamic Programming String+1
648. Replace Words	Solve	Medium	Facebook	Array Hash Table+2
649. Dota2 Senate	Solve	Medium	Valve	Greedy Queue+1
650. 2 Keys Keyboard	Solve	Medium	Amazon+1	Dynamic Programming Math
651. 4 Keys Keyboard	Solve	Medium	Microsoft	Dynamic Programming Math
652. Find Duplicate Subtrees	Solve	Medium	Amazon+2	Binary Tree Depth-First Search+2
654. Maximum Binary Tree	Solve	Medium	Amazon	Array Binary Tree+4
655. Print Binary Tree	Solve	Medium	Amazon+1	Binary Tree Breadth-First Search+2
658. Find K Closest Elements	Solve	Medium	Amazon+6	Array Binary Search+4
659. Split Array into Consecutive Subsequences	Solve	Medium	Bloomberg+1	Array Greedy+2
662. Maximum Width of Binary Tree	Solve	Medium	Amazon+4	Binary Tree Breadth-First Search+2
663. Equal Tree Partition	Solve	Medium	Amazon	Binary Tree Depth-First Search+1
665. Non-decreasing Array	Solve	Medium	Bloomberg	Array
666. Path Sum IV	Solve	Medium	Alibaba+1	Array Binary Tree+3
667. Beautiful Arrangement II	Solve	Medium	Google	Array Math
669. Trim a Binary Search Tree	Solve	Medium	Amazon+3	Binary Search Tree Binary Tree+2
670. Maximum Swap	Solve	Medium	Amazon+3	Greedy Math
672. Bulb Switcher II	Solve	Medium	Microsoft	Bit Manipulation Breadth-First Search+2
673. Number of Longest Increasing Subsequence	Solve	Medium	Amazon+6	Array Binary Indexed Tree+2
676. Implement Magic Dictionary	Solve	Medium	Facebook+1	Depth-First Search Design+3
677. Map Sum Pairs	Solve	Medium	Google	Design Hash Table+2
678. Valid Parenthesis String	Solve	Medium	Amazon+4	Dynamic Programming Greedy+2
681. Next Closest Time	Solve	Medium	Amazon+1	Backtracking Enumeration+2
684. Redundant Connection	Solve	Medium	Google+1	Breadth-First Search Depth-First Search+2
686. Repeated String Match	Solve	Medium	Google	String String Matching
687. Longest Univalue Path	Solve	Medium	Amazon+1	Binary Tree Depth-First Search+1
688. Knight Probability in Chessboard	Solve	Medium	Amazon+5	Dynamic Programming
690. Employee Importance	Solve	Medium	Apple+1	Array Breadth-First Search+3
692. Top K Frequent Words	Solve	Medium	Amazon+8	Bucket Sort Counting+5
694. Number of Distinct Islands	Solve	Medium	Amazon+3	Breadth-First Search Depth-First Search+3
695. Max Area of Island	Solve	Medium	Amazon+8	Array Breadth-First Search+3
698. Partition to K Equal Sum Subsets	Solve	Medium	Amazon+2	Array Backtracking+4
701. Insert into a Binary Search Tree	Solve	Medium	Amazon+2	Binary Search Tree Binary Tree+1
702. Search in a Sorted Array of Unknown Size	Solve	Medium	Google+1	Array Binary Search+1
707. Design Linked List	Solve	Medium	Amazon+4	Design Linked List