Lexicographically Smallest Palindrome
You are given a string s consisting of lowercase English letters, and you are allowed to perform operations on it. In one operation, you can replace a character in s with another lowercase English letter.
Your task is to make s a palindrome with the minimum number of operations possible. If there are multiple palindromes that can be made using the minimum number of operations, make the lexicographically smallest one.
A string a is lexicographically smaller than a string b of the same length if, in the first position where a and b differ, string a has a letter that appears earlier in the alphabet than the corresponding letter in b.
Return the resulting palindrome string.
Example 1
Input
s = "egcfe"Output
"efcfe"The minimum number of operations is 1, and changing
g produces the lexicographically smallest palindrome efcfe.Example 2
Input
s = "abcd"Output
"abba"The minimum number of operations is 2, and changing characters to form
abba gives the lexicographically smallest palindrome.Constraints
- 1 <= s.length <= 1000
- s consists of only lowercase English letters.