سوال من تمارين كتاب لغه جافا ولم اجد الحل

                         30

       47                               20

56            36               28         15

Binary tree 

Algorithm Write up. Write an algorithm to determine the cousins of a given node.

Note: - Cousins are node present at the same level but not having the same parent.
Example -
Cousin of 15 => 36, 56 (28 is not cousin)
Cousin of 28 => 36, 56 ( 67  is not cousin)
Cousin of 36 => 15, 28 ( 15 is not cousin)