LeetCode 2540: Minimum Common Value | 4 Approaches : Brute Force to Two Pointers | @DCodeThought

LeetCode POTD Solution Explained Step-by-Step | Java C++ Python Learn the thinking process from a basic Linear Search to the ultimate O(1) Space Two Pointers approach. Why Not → To → Why... 🔗 Problem Link (Code for all languages): https://dcodethought.vercel.app/problems/minimum-common-value-2540 Time : 0:00 : Intro 0:39 : Understanding & Decoding 2:00 : Method 1 — Brute Force 8:10 : Method 2 — HashSet 10:16 : Method 3 — Binary Search 11:52 : Method 4 — Two Pointers (Optimal) 📂 All POTD, Contest Solutions & Many More — Explore DCodeThought: https://dcodethought.vercel.app 🎥 WalkThrough Video: https://youtu.be/MYFQ7XAM4QA ━━━━━━━━━━━━━━━━━━━━ 🎯 My Goal With This Channel My aim is not just to show the final solution. My aim is to help you understand: ✔️ Why your solution doesn't work ✔️ Why the correct solution works On this channel, we don't jump directly from Problem → Answer. Instead, we go through the real thinking process. ━━━━━━━━━━━━━━━━━━━━ ❌ From Basic Linear Search (Brute Force) Comparing every element of array1 against array2. Even with an early break optimization, this can push our time complexity to: O(N × M) Too slow for larger constraints. ➡️ To HashSet Approach We realize we need faster lookups. Storing array1 inside a HashSet gives us: ✔️ O(1) lookups ✔️ O(N + M) Time Complexity But wait... ❌ O(N) Extra Space Can we do better? ➡️ To Binary Search We notice something important: The arrays are already sorted. So we can: • Iterate through the first array • Perform Binary Search on the second array Result: ✔️ O(N log M) Time ✔️ O(1) Space Better. But still not optimal. ✅ Finally Reaching Two Pointers (Optimal AC) Why search blindly? Since both arrays are already sorted, we can simply: • Place a pointer at the start of each array • Compare values • Move the pointer pointing to the smaller value Result: 🔥 O(N + M) Time 🔥 O(1) Space Elegant. Clean. Optimal. ━━━━━━━━━━━━━━━━━━━━ 📚 You Will Learn • How to leverage the "sorted" property of an array • How to trade space for time (and vice versa) across 4 different approaches • How to move from brute force nested loops to elegant Two Pointer thinking • Real interview & contest problem-solving mindset Because in real coding interviews and contests, Thinking matters more than memorizing solutions. Here we break down LeetCode POTD, contest problems, and important DSA questions with clear explanations so you can build strong problem-solving skills. If you want to improve your DSA logic, coding intuition, and interview problem solving, this channel is for you. Welcome to DCodeThought — where we focus on thinking, not just coding. ━━━━━━━━━━━━━━━━━━━━ 💻 Solutions Explained In: Java | C++ | Python 📌 Topics Covered: LeetCode POTD Array Manipulation Two Pointers Technique Binary Search HashSet / HashMaps Space-Time Complexity Trade-offs (O(N) vs O(1) Space) Data Structures & Algorithms Coding Interview Problems Competitive Programming Logic ━━━━━━━━━━━━━━━━━━━━ 🏷️ Tags: LeetCode 2540, 2540 LeetCode, Minimum Common Value, Minimum Common Value LeetCode, LeetCode 2540 solution, LeetCode 2540 Java, LeetCode 2540 C++, LeetCode 2540 Python, LeetCode POTD, LeetCode Problem of the Day, LeetCode daily challenge, LeetCode POTD today, Two Pointers, Binary Search, HashSet, Linear Search, Array Intersection, DCodeThought, DSA, Data Structures and Algorithms, DSA in Java, DSA in C++, DSA in Python, competitive programming, competitive programming tutorial, coding interview questions, FAANG interview preparation, software engineering interview, WA to AC, learn coding, DSA preparation, LeetCode Hindi solutions, coding intuition, logic building. ━━━━━━━━━━━━━━━━━━━━ 🔖 Hashtags: #LeetCode2540 #MinimumCommonValue #TwoPointers #BinarySearch #HashSet #LeetCodePOTD #DSA #DataStructures #Algorithms #CodingInterview #FAANGPrep #Java #CPP #Python #CompetitiveProgramming #DCodeThought #Programming #Coding #SoftwareEngineering #TechInterview #LearnCoding #CodingLogic #CodeNewbie #100DaysOfCode #LeetCodeDailyChallenge #ArrayAlgorithms