2815 - Max Pair Sum in an Array.

Easy

You are given a 0-indexed integer array nums. You have to find the maximum sum of a pair of numbers from nums such that the maximum digit in both numbers are equal.

Return the maximum sum or -1 if no such pair exists.

Example 1:

Input: nums = 51,71,17,24,42

Output: 88

Explanation:

For i = 1 and j = 2, numsi and numsj have equal maximum digits with a pair sum of 71 + 17 = 88.

For i = 3 and j = 4, numsi and numsj have equal maximum digits with a pair sum of 24 + 42 = 66.

It can be shown that there are no other pairs with equal maximum digits, so the answer is 88.

Example 2:

Input: nums = 1,2,3,4

Output: -1

Explanation: No pair exists in nums with equal maximum digits.

Constraints:

• 2 <= nums.length <= 100

• <code>1 <= numsi<= 10⁴</code>