You are given two strings `a`

and `b`

that consist of lowercase letters. In one operation, you can change any character in `a`

or `b`

to **any lowercase letter**.

Your goal is to satisfy **one** of the following three conditions:

**Every**letter in`a`

is**strictly less**than**every**letter in`b`

in the alphabet.**Every**letter in`b`

is**strictly less**than**every**letter in`a`

in the alphabet.**Both**`a`

and`b`

consist of**only one**distinct letter.

Return *the minimum number of operations needed to achieve your goal.*

**Example 1:**

Input:a = "aba", b = "caa"Output:2Explanation:Consider the best way to make each condition true: 1) Change b to "ccc" in 2 operations, then every letter in a is less than every letter in b. 2) Change a to "bbb" and b to "aaa" in 3 operations, then every letter in b is less than every letter in a. 3) Change a to "aaa" and b to "aaa" in 2 operations, then a and b consist of one distinct letter. The best way was done in 2 operations (either condition 1 or condition 3).

**Example 2:**

Input:a = "dabadd", b = "cda"Output:3Explanation:The best way is to make condition 1 true by changing b to "eee".

**Constraints:**

`1 <= a.length, b.length <= 10`

^{5}`a`

and`b`

consist only of lowercase letters.

class Solution {
public int minCharacters(String a, String b) {
}
}