LeetCode 448: Find All Numbers Disappeared in an Array – complete explanation in C++.
In this video, I explain how to find all missing numbers in an array using C++, focusing on interview thinking and the optimal in-place marking approach.
You’ll learn:
- Why brute force and sorting are inefficient
- How array indices can be used as markers
- In-place marking technique using negative values
- Step-by-step example walkthrough
- Complete C++ implementation
- Time and space complexity analysis
Timestamps:
00:00 Introduction & Problem Explanation
00:27 Example Walkthrough
01:14 Hash Set Logic
02:37 C++ Implementation
03:15 Code Execution & Output
Problem Link:
https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/
Approach:
- In-place index marking (Optimal)
Time Complexity: O(n)
Space Complexity: O(1) (excluding output array)
This is a very common array interview question asked in coding interviews and product-based companies.
This video is useful for:
- LeetCode beginners
- Array manipulation problems
- In-place algorithm interview questions
- DSA interview preparation
- C++ coding interviews
- FAANG interview preparation
Subscribe for clear explanations of LeetCode problems and interview-focused C++ solutions.
#leetcode #leetcode448 #array #c++
