human
I found an interesting problem on https://leetcode.com/problems/count-largest-group/:
Given an integer n. Each number from 1 to n is grouped according to the sum of its digits. 
Return how many groups have the largest size.
 
Example 1:
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.

Example 2:
Input: n = 2
Output: 2
Explanation: There are 2 groups [1], [2] of size 1.

Example 3:
Input: n = 15
Output: 6

Example 4:
Input: n = 24
Output: 5

 
Constraints:

1 <= n <= 10^4

I tried it in Python, but could not do it. Can you solve it?

Can you provide a the Python code you requested?
assistant
#Here is the Python code you requested.

class Solution:
    def countLargestGroup(self, n: int) -> int:
        memo = {1: 1}
        
        for i in range(2, n + 1):
            if not i % 10:
                memo[i] = memo[i // 10]
            else:
                memo[i] = memo[i - 1] + 1
        D = defaultdict(int)
        for k, v in memo.items():
            D[v] += 1
        res = 0
        
        for k in D.keys():
            if D[k] == max(D.values()):
                res += 1
        return res