You have been given a positive integer N. You need to find and print the Factorial of this number. The Factorial of a positive integer N refers to the product of all number in the range from 1 to N. You can read more about the factorial of a number here.

Input Format:
The first and only line of the input contains a single integer N denoting the number whose factorial you need to find.

Output Format
Output a single line denoting the factorial of the number N.

Constraints
1 ≤ N ≤ 10

SAMPLE INPUT
2

SAMPLE OUTPUT
2

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