Factorial Computation

This problem requires you to compute the factorial of a non-negative integer n. The factorial is defined as

\( n! = \prod_{i=1}^{n} i \)

with the special case that \(0! = 1\). You need to read an integer from standard input and output its factorial on standard output.

inputFormat

The input consists of a single non-negative integer n (0 ≤ n ≤ 20) on a single line.

outputFormat

Output the factorial of the given number n on standard output.

0

1