Cracking LeetCode 2784: Is This Array "Good"? Let's Find Out! Hey everyone! Vansh2710 here, your friendly neighborhood competitive programmer and technical writing enthusiast! Today, we're diving into a fun little LeetCode problem that's perfect for beginners to sharpen their logical thinking: 2784. Check if Array is Good . Don't let the "permutation" jargon scare you. We'll break it down step by step and discover an elegant solution together. Ready to level up your LeetCode game? Let's go! 🚀 Problem Explanation: What Makes an Array "Good"? Imagine you have a special kind of array called base[n] . This base[n] array always looks like this: [1, 2, ..., n - 1, n, n] In plain English, it's an array of length n + 1 that contains: All numbers from 1 up to n - 1 appear exactly once . The number n appears exactly twice . For example: If n = 1 , then base[1] = [1, 1] . (Length 1+1=2) If n = 3 , then base[3] = [1, 2, 3, 3] . (Length 3+1=4) If n = 5 , then base[5] = [1, 2, 3, 4, 5, 5] .…