DS and Algo Interview Questions

In the ever-evolving tech industry, data structure and algorithm knowledge plays a crucial role in landing top-notch job offers. As we approach 2023, it’s essential to stay updated and well-prepared for data structure and algorithm interviews. In this blog post, we’ll provide you with a comprehensive guide that covers the key concepts, problem-solving techniques, and tips to excel in your upcoming interviews.

Table of Contents:

1 Integer

2 Strings

  • Reverse String (LC 344)
  • Longest Common Prefix (LC 14)
  • Reverse Words in a String (LC 151)
  • Longest Palindromic substring (LC 5)
  • Longest substring without repeating characters (LC 3)
  • Valid Parentheses (LC 20)
  • Decode String (LC 394)
  • Word Break (LC 139)
  • Valid Anagram (LC 242)
  • Repeated DNA Sequences (LC 187)
  • Integer to English Words (LC 273)
  • Above String related questions solution

3 Arrays

  • Sort Colors (LC 75)
  • Merge Sorted Array (LC 80)
  • Two Sum (LC 1)
  • Binary Search (LC 704)
  • Length of Last Word (LC 58)
  • Plus One (LC 66)
  • Jump Game (LC 55)
  • Move Zeroes (LC 283)
  • Asteroid Collision (LC 753)
  • Kids with Greatest Number of Candies (LC 1431)
  • Average Salary Excluding the Minimum and Maximum (LC 1491)
  • Best Time to Buy and Sell Stock (LC 122)
  • Best Time to Buy and Sell Stock II(LC 122)
  • Find All Disappeared Numbers in an Array (LC 448)
  • Find All Duplicates Numbers in an Array (LC 442)
  • Pascal’s Triangle (LC 118)
  • Pascal’s Triangle (LC 119)
  • Sequential Digits (LC 1291)
  • Product of Array Except self (LC 238)
  • Gas Station (LC 134)
  • Rotate Array (LC 189)
  • Minimum Domino Rotations For Equal Row (LC 1007)
  • Subarray Product Less than K (LC 713)
  • Jump Game III (LC 1306)
  • K-Diff Pairs in an Array (LC 532)
  • Majority Element Solutions (LC 169)
  • House Robber II (LC 213)
  • Maximum Product Subarray (LC 152)
  • Group Anagrams (LC 49)
  • 132 Pattern 3 solution (LC 456)
  • First Missing Positive (LC 41)
  • Sliding Window Maximum (LC 239)
  • Median of Two Sorted Arrays (LC 4)

4 Two Pointer

  • Is Subsequence (LC 392)
  • Valid Palindrome (LC 125)
  • Squares of a Sorted Array (LC 977)
  • Remove Duplicates from Sorted Array (LC 26)
  • Trapping Rain Water (LC 42)
  • 3 Sum (LC 15)

5 Famous Algorithm

  • Kaden’s Algorithm -Maximum Subarray (LC 53)

6 Sorting Algorithm

  • Merge Sort Sort an Array (LC 912)
  • Quick Sort Sort an Array (LC 912)

7 2D Arrays Matrix

  • Rotate Image (LC 48)
  • Remove Covered Interval (LC 1288)
  • Merge Intervals (LC 56)
  • Matrix Diagonal Sum (LC 1572)
  • Search a 2D Matrix (LC 74)
  • Set Matrix Zeroes (LC 73)
  • Spiral Matrix (LC 54)

8 Linked List

  • Flatten Binary Tree to Linked List (LC 114)
  • Add Two Linked Lists Add Two Numbers II (LC 445)
  • Odd Even Linked List (LC 238)
  • Rotate List (LC 61)
  • Swap Nodes In Pairs [Iterative] (LC 24)
  • Swap Nodes In Pairs [Recursive] (LC 24)
  • Middle of a Linked List (LC 876)
  • Linked List Cycle II (LC 142)
  • Linked List Cycle (LC 141)
  • Reverse Linked List [Iterative+Recursive] (LC 206)
  • Merge Two Sorted Lists (LC 21)
  • Intersection of Two Linked List (LC 160)
  • Palindrome Linked List (LC 234)
  • Copy List with Random Pointer (LC 138)
  • Reverse Nodes in k-group (LC 25)
  • LRU Cache (LC 146)
  • Design Linked List (LC 707)

9 Tree, Stack, Queue

  • Binary Tree Preorder Traversal Recursive + Iterative Solution (LC 144)
  • Binary Tree Inorder Traversal Recursive + Iterative Solution (LC 94)
  • Binary Tree Post Order Traversal Recursive + Iterative (LC 145)
  • Level Order Traversal Binary Tree Recursive + Iterative (LC 102)
  • Binary Tree Zigzag Level Order Traversal Recursive + Iterative (LC 103)
  • Convert Sorted Array to Binary Search Tree (LC 108)
  • Construct Binary Search Tree from Preorder Traversal (LC 1008)
  • Diameter of Binary Tree (LC 543)
  • Range Sum of BST (LC 938)
  • Same Tree (LC 100)
  • Flipinvert Binary Tree (LC 226)
  • Minimum Depth of Binary Tree (LC 111)
  • Maximum Depth of Binary Tree (LC 104)
  • Balanced Binary Tree (LC 110)
  • Insert into a Binary Search Tree (LC 701)
  • Serialize and deserialize binary tree (LC 297)
  • Binary Tree Maximum Path Sum (LC 124)
  • Implement Trie (LC 208)
  • Validate Binary Search Tree (LC 98)
  • Robber House III (LC 337)
  • Lowest Common Ancestor of Binary Tree (LC 236)

10 Graph

  • Number of Islands (LC 200)
  • Clone a Graph (LC 133)

11 Fibonacci Sequence

  • Climbing Stairs

12 Backtracking Recursion

  • Generate Parentheses (LC 22)
  • Combination Sum (LC 39)
  • Combination Sum III (LC 216)
  • Subsets (LC 78)

13 Dynamic Programming

  • Climbing Stairs (LC 70)
  • Fibonacci Number 3 (LC 509)
  • Minimum Path Sum (LC 64)
  • House Robber (LC 198)
  • Longset Increasing Subsequence (LC 300)
  • Best Time to Buy and Sell Stock IV (LC 188)
  • Longest Common Subsequence (LC 1143)
  • Edit Distance (LC 72)
  • Wilcard Matching (LC 44)
  • Regular Expression Matching (LC 10)

14 Bit Manipulation

  • Number of 1 Bits (LC 191)
  • Find the Difference (LC 389)
  • Reverse Bits (LC 190)
  • Hamming Distance (LC 461)
  • Complement of Base 10 Integer (LC 1009)
  • Counting Bits (LC 338)
  • Sum of Two Integers (LC 371)
  • Divide Two Integers (LC 29)

15 Design

  • Design a Stack MinStack (LC 155)

16 System Design

17 System Scaling