LeetCode 136: Single Number – complete explanation in C++.
In this video, I explain how to solve the Single Number problem step by step using C++, focusing on interview thinking and the XOR bit manipulation approach.
You’ll learn:
- Why XOR works for the Single Number problem
- Bit manipulation intuition (no memorization)
- Step-by-step dry run with examples
- Complete C++ implementation
- Time and space complexity analysis
Problem Link:
https://leetcode.com/problems/single-number/description/
Timestamps:
00:00 Introduction & Problem Explanation
00:38 Example Walkthrough
01:10 Brute Force Idea (Why It Fails)
02:26 Sorting Approach
03:27 Hash Map Approach
04:46 Bit Manipulation (XOR) Intuition – Core Idea
07:32 C++ Implementation
07:55 Code Execution & Output
Approaches Covered:
1) XOR (Bit Manipulation) – Optimal approach
2) Brief discussion of brute force ideas
Time Complexity: O(n)
Space Complexity: O(1)
This is a very common interview question asked in coding interviews and product-based companies.
This video is useful for:
- LeetCode beginners
- Bit manipulation problems
- XOR interview questions
- DSA interview preparation
- C++ coding interviews
- FAANG interview preparation
Subscribe for clear explanations of LeetCode problems and interview-focused C++ solutions.
#leetcode #leetcode136 #singlenumber #bitmanipulation #c++
