The REAL Way to Solve 3SUM | Why Your Approach Fails & How To Fix It | Day 2 скачать в хорошем качестве

The REAL Way to Solve 3SUM | Why Your Approach Fails & How To Fix It | Day 2

Solving 3SUM isn’t just about finding three numbers that add up to zero — it’s about understanding a core interview pattern used in dozens of problems: ✔ two-pointer scanning ✔ search-space reduction ✔ duplicate control ✔ and converting k-sum problems into structured steps. This video is a complete breakdown of that pattern. Instead of throwing code at you, I walk through how to think about 3SUM: how to reduce brute force into a predictable O(n²) strategy, why hash-based solutions often mislead beginners, and how the two-pointer pattern actually works under the hood. If you’ve ever struggled with: – pointer movement – repeated triplets – negative + positive balancing – or the general “k-sum” mindset… this video will finally give you clarity. 🌟 What You’ll Take Away A reusable framework to solve 3SUM, 4SUM, k-SUM How to detect when two pointers are the optimal strategy How to eliminate duplicate results without hacks How sorted arrays reveal relationships that unsorted arrays hide Confidence to explain AND defend your logic in interviews 🧠 Why 3SUM Matters This single question teaches patterns used in: • 2-pointer problems • subarray sum questions • pair/triplet counting problems • target-based searching • pointer collision technique If you master 3SUM properly, a whole category of DSA questions becomes easier. 🔗 Join the Learning Community If you want accountability, help from other learners, and daily practice: 👉 Join our Discord:   / discord   I’m not teaching from above — I’m learning consistently, same as you. Let’s build this journey together. 💾 Resources Code, notes, extra examples: 👉 https://github.com/dojocodex/dailydsa ⏭ Recommended Videos To reinforce this pattern, watch next: • Two Sum (foundation of 3SUM)    • 365 Days to Crack MAANG | Welcome to DojoC...   Timestamps: 00:00 Intro 01:06 Problem statement 02.28 High level thinking 03:41 Brute Force Approach 04:20 Brute Force Pseudo Code 06:22 Optimization Approach 08:23 Better Approach 10:49 Hashset Pseudo Code 12:58 Hashset approach dry run 15:51 Hashset approach coding 18:39 Optimal approach 21:57 Two pointer pseudo code 24:56 optimal leetcode 29:00 Wrap Up #3sum #leetcode #twopointers #dsa #codinginterview #interviewpreparation #datastructures #algorithms #python #cpp #javascript