Subsets (1) X86812

Write a program that, given $n$ different words $s_1, \dots, s_n$, prints all the subsets that can be made up with the words.

Input

Input consists of a number $n > 0$, followed by $s_1, \dots, s_n$.

Output

Print all the subsets that can be made up with $s_1, \dots, s_n$.

Information about the checker

You can print in any order both the solutions and the elements inside each solution.