Factorial

Problem Description

Given a positive integer $n$, compute and output the value of $1 \times 2 \times 3 \times \dots \times n$.

(Terminology: the factorial is the product of all integers from $1$ to $n$, denoted by $n!$.)

Input Format

One integer $n$.

Output Format

One integer: the value of $1 \times 2 \times 3 \times \dots \times n$.

Sample Input

3

Sample Output

6

Constraints

$1 \le n \le 10$