Class Solution

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    public final class Solution
    
                        

    3272 - Find the Count of Good Integers\.

    Hard

    You are given two positive integers n and k.

    An integer x is called k-palindromic if:

    • x is a palindrome.

    • x is divisible by k.

    An integer is called good if its digits can be rearranged to form a k-palindromic integer. For example, for k = 2, 2020 can be rearranged to form the k-palindromic integer 2002, whereas 1010 cannot be rearranged to form a k-palindromic integer.

    Return the count of good integers containing n digits.

    Note that any integer must not have leading zeros, neither before nor after rearrangement. For example, 1010 cannot be rearranged to form 101.

    Example 1:

    Input: n = 3, k = 5

    Output: 27

    Explanation:

    Some of the good integers are:

    • 551 because it can be rearranged to form 515.

    • 525 because it is already k-palindromic.

    Example 2:

    Input: n = 1, k = 4

    Output: 2

    Explanation:

    The two good integers are 4 and 8.

    Example 3:

    Input: n = 5, k = 6

    Output: 2468

    Constraints:

    • 1 <= n <= 10

    • 1 <= k <= 9

    • Nested Class Summary

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      Modifier and Type Class Description
    • Field Summary

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    • Constructor Summary

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      Constructor Description
      Solution()
    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description
    • Method Summary

      Modifier and Type Method Description
      final Long countGoodIntegers(Integer n, Integer k)
      • Methods inherited from class java.lang.Object

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