3Sum - Two Pointer Trick That Cracked Google Interview | LeetCode 15 | AI/ML Interview Prep

🔍 3Sum is one of Google's most frequently asked interview problems — and the O(n²) two-pointer approach after sorting is the trick that separates candidates. This video explains it visually. What you'll learn: ✅ Why brute force O(n³) fails and how sorting + two pointers gives O(n²) ✅ How to fix the pointer after fixing one element ✅ Duplicate skipping logic — the step most people miss ✅ Visual walkthrough: [-1, 0, 1, 2, -1, -4] → triplets that sum to 0 ✅ Clean Python implementation 🎯 This exact problem was asked in Google's ML Engineer coding round. Nail the duplicate-skip logic and you're golden. 🧠 Practice this problem yourself: 👉 https://codedive.in/3sum 🚀 codedive.in — 207 curated DSA problems for AI/ML engineers. Visual explanations, Python solutions, interview strategy. ━━━━━━━━━━━━━━━━━━━━━━━━━━ ⏱ Timestamps: 0:00 - Problem Statement 0:30 - Why Brute Force Fails 1:00 - Sort + Two Pointer Intuition 1:45 - Duplicate Skipping Logic 2:30 - Visual Walkthrough 3:15 - Python Code 3:45 - Complexity Analysis ━━━━━━━━━━━━━━━━━━━━━━━━━━ #3Sum #LeetCode15 #TwoPointer #GoogleInterview #AIMLEngineer #LeetCode #CodingInterview #PythonDSA #DSAInterview