Output Format

Output a single integer in one line: the number of pairing schemes where among the $n$ couples, at most $k$ couples have the girl taller than the boy.

3 0
178
188
176
168
178
170

4

Hint

Constraints: For $100\%$ of the testdata, $1 \le n \le 200$, $0 \le k \le n$, and all heights are positive integers not greater than $10^9$.

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