In the alphabet of the language of the tribe «Tumba-Yumba» four letters: "K", "L", "M" and "N". We need to display all possible words consisting of n letters (n > 1) in which the second letter is «K». Count the number of such words.
Examples
| # |
Input |
Output |
| 1 |
2 |
KK
LK
MK
NK
4 |
(c) K.Yu. Polyakov