## A Rook Problem

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Points: 10
Time limit: 1.0s
Memory limit: 64M

Author:
Problem type

Junyi is an avid chess player. He would like to know how many ways it is possible to place $$K$$ rooks on an $$N \times N$$ chessboard such that no rook are in an attacking position.

A rook can only move horizontally and vertically from its current position and two rooks are in an attacking position if one is on the path of the other.

#### Input Specification

The first line will contain two integers $$N, K\ (1 \le N \le 10, 1 \le K \le N^2)$$.

#### Output Specification

The number of ways to place $$K$$ rooks on an $$N \times N$$ chessboard such that no rooks are in an attacking position.

#### Sample Input

4 4

#### Sample Output

24