50 General Coding Questions

Top 50 Coding Interview Questions You Should Know

Here’s a list of 50 coding interview questions that cover a range of topics. These questions are commonly asked during technical interviews for software engineering and programming positions. Keep in mind that interview questions can vary, and it’s essential to practice problem-solving and coding regularly. Additionally, understanding data structures, algorithms, and problem-solving techniques will greatly help you in tackling coding interviews.

Arrays and Strings:

  1. Two Sum
  2. Valid Palindrome
  3. Longest Substring Without Repeating Characters
  4. Reverse String
  5. String to Integer (atoi)
  6. Container With Most Water
  7. Longest Common Prefix
  8. Rotate Array
  9. Group Anagrams
  10. Valid Parentheses

Linked Lists:

  1. Merge Two Sorted Lists
  2. Reverse Linked List
  3. Remove Nth Node From End of List
  4. Add Two Numbers
  5. Palindrome Linked List
  6. Intersection of Two Linked Lists

Stacks and Queues:

  1. Valid Parentheses
  2. Min Stack
  3. Implement Queue using Stacks
  4. Largest Rectangle in Histogram

Trees and Graphs:

  1. Binary Tree Inorder Traversal
  2. Validate Binary Search Tree
  3. Maximum Depth of Binary Tree
  4. Symmetric Tree
  5. Binary Tree Level Order Traversal
  6. Course Schedule
  7. Clone Graph

Sorting and Searching:

  1. Merge Sort
  2. Quick Sort
  3. Binary Search
  4. Search in Rotated Sorted Array

Dynamic Programming:

  1. Fibonacci Sequence
  2. Climbing Stairs
  3. Longest Increasing Subsequence
  4. 0/1 Knapsack Problem
  5. Coin Change

Recursion:

  1. Factorial
  2. Power of X to the Y
  3. Print All Permutations of a String

Bit Manipulation:

  1. Single Number
  2. Counting Bits

Hashing:

  1. Two Sum
  2. Longest Substring Without Repeating Characters
  3. Group Anagrams

Design and Object-Oriented Programming:

  1. Design a Parking Lot
  2. Implement a LRU Cache
  3. Design Twitter
  4. Design a TinyURL Service
  5. Design a Chess Game
  6. Design a System to Manage Courses and Students

Remember that the key to excelling in coding interviews is not just memorizing solutions but understanding the underlying concepts and problem-solving techniques. Practice solving problems on platforms like LeetCode, HackerRank, and CodeSignal, and consider reviewing your solutions to understand how you can optimize them further.