Class Solution


  • public class Solution
    extends Object
    526 - Beautiful Arrangement.

    Medium

    Suppose you have n integers labeled 1 through n. A permutation of those n integers perm ( 1-indexed ) is considered a beautiful arrangement if for every i (1 <= i <= n), either of the following is true:

    • perm[i] is divisible by i.
    • i is divisible by perm[i].

    Given an integer n, return the number of the beautiful arrangements that you can construct.

    Example 1:

    Input: n = 2

    Output: 2

    Explanation:

    The first beautiful arrangement is [1,2]:

    • perm[1] = 1 is divisible by i = 1

    • perm[2] = 2 is divisible by i = 2

    The second beautiful arrangement is [2,1]:

    • perm[1] = 2 is divisible by i = 1

    • i = 2 is divisible by perm[2] = 1

    Example 2:

    Input: n = 1

    Output: 1

    Constraints:

    • 1 <= n <= 15
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • countArrangement

        public int countArrangement​(int n)