package main

import "fmt"

func main() {
	const mod int = 1e12
	var n int
	fmt.Scan(&n)

	fact := 1
	isOverflown := false
	for i := 1; fact != 0 && i <= n; i++ {
		if fact*i >= mod {
			isOverflown = true
		}
		fact *= i
		fact %= mod
	}

	if !isOverflown {
		fmt.Println(fact)
	} else {
		fmt.Printf("%012d\n", fact)
	}
}