Unique Subsets

Given two non-negative integers \(n\) and \(k\), your task is to compute the number of unique subsets of size \(k\) that can be selected from \(n\) records. This is equivalent to calculating the binomial coefficient:

\[ \binom{n}{k} = \frac{n!}{k!(n-k)!} \]

You need to read from standard input and output the result to standard output.

inputFormat

The input consists of a single line containing two integers \(n\) and \(k\) separated by a space.

outputFormat

Output a single integer representing \(\binom{n}{k}\).

5 3

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