Largest Digit Sum Group Finder
Count Largest Group — Group Numbers by Digit Sum Problem Statement You're given a positive integer n . Group all numbers from 1 to n based on the sum of their digits . Your task is to find how many groups have the largest size (i.e., most numbers). Input: n = 13 Output: 4 Explanation: There are 9 groups in total, they are grouped according sum of its digits of numbers from 1 to 13: [1,10], [2,11], [3,12], [4,13], [5], [6], [7], [8], [9]. There are 4 groups with largest size. Best Technique – Digit Grouping with Hashing / Array Optimization This problem looks simple, but under the hood, it tests your ability to: Understand digit operations Use maps or arrays efficiently Find maximums intelligently Let’s explore multiple ways to solve this, from brute force to optimal, and see how each one helps us understand the problem better. Different Approaches: Approach 1: Brute Force using List Grouping Group every number by the digit sum and store fu...