package main

import "fmt"

var mod int

func fact(n int) int {
	if n == 0 {
		return 1
	}
	return (n * fact(n-1)) % mod
}

func main() {
	mod = pow(10, 12)

	var n int
	fmt.Scan(&n)
	if n >= 50 {
		fmt.Println(0)
	} else {
		fmt.Println(fact(n))
	}

}

func pow(a, b int) int {
	res := 1
	for range make([]struct{}, b) {
		res *= a
	}
	return res
}