Given a palindromic string palindrome, replace exactly one character by any lowercase English letter so that the string becomes the lexicographically smallest possible string that isn't a palindrome.
After doing so, return the final string. If there is no way to do so, return the empty string.
Example 1:
Input: palindrome = "abccba" Output: "aaccba"
Example 2:
Input: palindrome = "a" Output: ""
Constraints:
<li><code>1 <= palindrome.length <= 1000</code></li>
<li><code>palindrome</code> consists of only lowercase English letters.</li>