#377. Loop: n! (1·2·...·n)
You get a positive integer n. Use a `for` loop to find **n! (1·2·...·n)**.
### Input
One integer n (1 ≤ n ≤ 20).
### Output
One integer.
Examples
Input
14
Output
87178291200
Input
9
Output
362880
💡 You can solve it with Python, JavaScript or blocks. Read the input line by line with input(). Don't print a question (like input("Number: ")). Print exactly what the output asks for, nothing more.