🚀 LeetCode 15: 3Sum Explained Step by Step in C++ | Optimal O(n²) Two Pointer Solution
In this video, we solve one of the most asked coding interview problems — LeetCode 15: 3Sum — using the optimal Sorting + Two Pointer approach. This tutorial includes a complete line-by-line code explanation, dry run, duplicate handling logic, and time complexity analysis to help you fully understand the problem and crack coding interviews confidently.
You’ll learn:
✅ How the Two Pointer Technique works
✅ Why sorting is important in 3Sum
✅ How to avoid duplicate triplets
✅ Full C++ code walkthrough
✅ Time Complexity and Space Complexity
✅ Interview tips for LeetCode problems
Problem Statement:
Given an integer array nums, return all unique triplets [nums[i], nums[j], nums[k]] such that:
nums[i] + nums[j] + nums[k] == 0
This video is perfect for:
DSA Preparation
LeetCode Interview Questions
Coding Interview Preparation
Beginners learning Two Pointers
C++ Programming Practice
Topics Covered:
LeetCode 15, 3Sum, Arrays, Two Pointers, Sorting, C++ STL, Coding Interviews, DSA, Algorithms, Competitive Programming
#leetcode #3sum #dsa #codinginterview #cplusplus #twopointers #leetcode15 #algorithms #programming #interviewprep
