1796. Second Largest Digit in a String

https://leetcode.com/problems/second-largest-digit-in-a-string

Description

Given an alphanumeric string s, return the second largest numerical digit that appears in s, or -1 if it does not exist.

An alphanumericstring is a string consisting of lowercase English letters and digits.

Example 1:

**Input:** s = "dfa12321afd"
**Output:** 2
**Explanation:** The digits that appear in s are [1, 2, 3]. The second largest digit is 2.

Example 2:

**Input:** s = "abc1111"
**Output:** -1
**Explanation:** The digits that appear in s are [1]. There is no second largest digit. 

Constraints:

• 1 <= s.length <= 500

• s consists of only lowercase English letters and/or digits.

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