3518. Smallest Palindromic Rearrangement II

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