3300 - Minimum Element After Replacement With Digit Sum (Easy)

Problem Link

https://leetcode.com/problems/minimum-element-after-replacement-with-digit-sum/

Problem Statement

You are given an integer array nums.

You replace each element in nums with the sum of its digits.

Return the minimum element in nums after all replacements.

Example 1:

Input: nums = [10,12,13,14]

Output: 1

Explanation:

nums becomes [1, 3, 4, 5] after all replacements, with minimum element 1.

Example 2:

Input: nums = [1,2,3,4]

Output: 1

Explanation:

nums becomes [1, 2, 3, 4] after all replacements, with minimum element 1.

Example 3:

Input: nums = [999,19,199]

Output: 10

Explanation:

nums becomes [27, 10, 19] after all replacements, with minimum element 10.

Constraints:

• 1 <= nums.length <= 100
• 1 <= nums[i] <= 10^4

Approach 1: Brute Force

For each element, we calculate the digit sum and use $res$ to keep track of the minimum one.

class Solution:
    def minElement(self, nums: List[int]) -> int:
        res = 10 ** 9
        for x in nums:
            s = 0
            while x > 0:
                s += x % 10
                x //= 10
            res = min(res, s)
        return res