You are given a palindromic string s and an integer k.
Return the k-th lexicographically smallest palindromic permutation of s. If there are fewer than k distinct palindromic permutations, return an empty string.
Note: Different rearrangements that yield the same palindromic string are considered identical and are counted once.
Example 1:
Input: s = "abba", k = 2
Output: "baab"
Explanation:
"abba" are "abba" and "baab"."abba" comes before "baab". Since k = 2, the output is "baab".Example 2:
Input: s = "aa", k = 2
Output: ""
Explanation:
"aa".k = 2 exceeds the number of possible rearrangements.Example 3:
Input: s = "bacab", k = 1
Output: "abcba"
Explanation:
"bacab" are "abcba" and "bacab"."abcba" comes before "bacab". Since k = 1, the output is "abcba".
Constraints:
1 <= s.length <= 104s consists of lowercase English letters.s is guaranteed to be palindromic.1 <= k <= 106