Problem:
Factorial

Write a program which reads an integer n and prints the factorial of n. You can assume that n ≤ 20.

Input

An integer n (1 ≤ n ≤ 20) in a line.

Output

Print the factorial of n in a line.

Sample Input

5

Output for the Sample Input

120

Solution in JAVA (judge verdict: Accepted)

import java.util.*;
 
class Main {
    public static void main(String args[]) {
        Scanner sc =new Scanner(System.in);
		int n= sc.nextInt();
		int i;
		long s=1;
		
		for(i=2;i<=n;i++)
		s*=i;
		
		System.out.println(s);
        
    }
}