You are given a string s consisting only of lowercase English letters.
You can perform the following operation any number of times (including zero):
Choose any character c in the string and replace every occurrence of c with the next lowercase letter in the English alphabet.
Return the minimum number of operations required to transform s into a string consisting of only 'a' characters.
Note: Consider the alphabet as circular, thus 'a' comes after 'z'.
Example 1:
Input: s = "yz"
Output: 2
Explanation:
'y' to 'z' to get "zz".'z' to 'a' to get "aa".Example 2:
Input: s = "a"
Output: 0
Explanation:
"a" only consists of 'a' characters. Thus, the answer is 0.
Constraints:
1 <= s.length <= 5 * 105s consists only of lowercase English letters.