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
1. Two Sum	Solve	Easy	Accenture+29	Array Hash Table
9. Palindrome Number	Solve	Easy	Accenture+8	Math
13. Roman to Integer	Solve	Easy	Accenture+18	Hash Table Math+1
14. Longest Common Prefix	Solve	Easy	Adobe+9	String Trie
20. Valid Parentheses	Solve	Easy	Adobe+25	Stack String
21. Merge Two Sorted Lists	Solve	Easy	Accenture+9	Linked List Recursion
26. Remove Duplicates from Sorted Array	Solve	Easy	Adobe+8	Array Two Pointers
27. Remove Element	Solve	Easy	Adobe+4	Array Two Pointers
28. Find the Index of the First Occurrence in a String	Solve	Easy	Amazon+4	String String Matching+1
35. Search Insert Position	Solve	Easy	Adobe+8	Array Binary Search
58. Length of Last Word	Solve	Easy	Amazon+1	String
66. Plus One	Solve	Easy	Adobe+5	Array Math
67. Add Binary	Solve	Easy	Adobe+5	Bit Manipulation Math+2
69. Sqrt(x)	Solve	Easy	Adobe+6	Binary Search Math
70. Climbing Stairs	Solve	Easy	Adobe+8	Dynamic Programming Math+1
83. Remove Duplicates from Sorted List	Solve	Easy	Adobe+4	Linked List
88. Merge Sorted Array	Solve	Easy	Amazon+9	Array Sorting+1
94. Binary Tree Inorder Traversal	Solve	Easy	Adobe+13	Binary Tree Depth-First Search+2
100. Same Tree	Solve	Easy	Amazon+5	Binary Tree Breadth-First Search+2
101. Symmetric Tree	Solve	Easy	Adobe+7	Binary Tree Breadth-First Search+2
104. Maximum Depth of Binary Tree	Solve	Easy	Amazon+7	Binary Tree Breadth-First Search+2
108. Convert Sorted Array to Binary Search Tree	Solve	Easy	Amazon+4	Array Binary Search Tree+3
110. Balanced Binary Tree	Solve	Easy	Adobe+4	Binary Tree Depth-First Search+1
111. Minimum Depth of Binary Tree	Solve	Easy	Acko+15	Binary Tree Breadth-First Search+2
112. Path Sum	Solve	Easy	Amazon+4	Binary Tree Breadth-First Search+2
118. Pascal's Triangle	Solve	Easy	Adobe+17	Array Dynamic Programming
119. Pascal's Triangle II	Solve	Easy	Adobe+3	Array Dynamic Programming
121. Best Time to Buy and Sell Stock	Solve	Easy	Adobe+30	Array Dynamic Programming
125. Valid Palindrome	Solve	Easy	Adobe+8	String Two Pointers
136. Single Number	Solve	Easy	Adobe+8	Array Bit Manipulation
141. Linked List Cycle	Solve	Easy	42gearMobilitySystems+131	Hash Table Linked List+1
144. Binary Tree Preorder Traversal	Solve	Easy	Adobe+2	Binary Tree Depth-First Search+2
145. Binary Tree Postorder Traversal	Solve	Easy	Facebook+1	Binary Tree Depth-First Search+2
157. Read N Characters Given Read4	Solve	Easy	Amazon+4	Array Interactive+1
160. Intersection of Two Linked Lists	Solve	Easy	Adobe+7	Hash Table Linked List+1
163. Missing Ranges	Solve	Easy	Facebook	Array
168. Excel Sheet Column Title	Solve	Easy	Adobe+24	Math String
169. Majority Element	Solve	Easy	Adobe+8	Array Counting+3
170. Two Sum III - Data structure design	Solve	Easy	LinkedIn	Array Data Stream+3
171. Excel Sheet Column Number	Solve	Easy	Apple+2	Math String
175. Combine Two Tables	Solve	Easy	Adobe+6	Database
181. Employees Earning More Than Their Managers	Solve	Easy	Amazon+7	Database
182. Duplicate Emails	Solve	Easy	Adobe+2	Database
183. Customers Who Never Order	Solve	Easy	Adobe+3	Database
190. Reverse Bits	Solve	Easy	Apple+4	Bit Manipulation Divide and Conquer
191. Number of 1 Bits	Solve	Easy	Amazon+6	Bit Manipulation Divide and Conquer
193. Valid Phone Numbers	Solve	Easy	-	Shell
195. Tenth Line	Solve	Easy	-	Shell
196. Delete Duplicate Emails	Solve	Easy	Amazon+3	Database
197. Rising Temperature	Solve	Easy	Adobe+5	Database