java.lang.Object
g3201_3300.s3272_find_the_count_of_good_integers.Solution

public class Solution extends Object
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
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • countGoodIntegers

      public long countGoodIntegers(int n, int k)