Matrioshkas
Very easy
Execution time limit is 0.5 seconds
Runtime memory usage limit is 64 megabytes
On the table are N matreshkas of different sizes. Smaller doll can be placed inside the larger one that, in turn, into still greater, and so on.
How many ways can be placed inside the other part of the dolls to remain exactly K matreshkas?
Input
The input file contains integers N and K (1 ≤ K ≤ N ≤ 12).
Output
You want to display the output file a single integer - the desired number of ways.
Examples
Input #1
Answer #1
Submissions 181
Acceptance rate 24%