Description

In Xiaoming's school, there are only $m$ spots available for the city competition, but $n$ people have registered.
The teacher is troubled and doesn't know who to select, so he's looking for an absolutely fair way to decide.
He plans to have everyone draw lots, where $m$ lots mean "go" and the rest mean "don't go".
Xiaoming really wants to know how many different possible outcomes there are from the drawing. Please design a program to help Xiaoming!

Input Format

The first line contains two integers $n$,$m$, as described in the problem.
The next $n$ lines each contain a string $S$, representing a person's name. $1≤m≤n≤15$.

Output Format

Output several lines, each containing $m$ strings representing the names of the selected people.
Within each solution, output the names in the order they were read in. The order of different solutions can be arbitrary.

Sample

3 2
xiaowang
xiaoA
xiaoli

xiaowang xiaoA
xiaowang xiaoli
xiaoA xiaoli