문제

코드

import java.util.Scanner;

public class q27433 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        System.out.println(factorial(N));
    }
    public static long factorial(int n) {
        if(n < 1) {
            return 1;
        } else {
            return factorial(n-1) * n;
        }
    }
}