Package g3501_3600.s3518_smallest_palindromic_rearrangement_ii

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    3518 - Smallest Palindromic Rearrangement II.

    Hard

    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:

    • The two distinct palindromic rearrangements of "abba" are "abba" and "baab".

    • Lexicographically, "abba" comes before "baab". Since k = 2, the output is "baab".

    Example 2:

    Input: s = "aa", k = 2

    Output: ""

    Explanation:

    • There is only one palindromic rearrangement: "aa".

    • The output is an empty string since k = 2 exceeds the number of possible rearrangements.

    Example 3:

    Input: s = "bacab", k = 1

    Output: "abcba"

    Explanation:

    • The two distinct palindromic rearrangements of "bacab" are "abcba" and "bacab".

    • Lexicographically, "abcba" comes before "bacab". Since k = 1, the output is "abcba".

    Constraints:

    • <code>1 <= s.length <= 10<sup>4</sup></code>

    • s consists of lowercase English letters.

    • s is guaranteed to be palindromic.

    • <code>1 <= k <= 10<sup>6</sup></code>

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final String smallestPalindrome(String inputStr, Integer k)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait