[백준] 10872번 팩토리얼 문제! (bronze 5

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

public class Main {

	public static void main(String[] args) throws IOException    {
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		BufferedWriter bw=new BufferedWriter(new OutputStreamWriter(System.out));
		int num=Integer.parseInt(br.readLine());
		System.out.println(factorial(num));
		
	
	}
	
	public static int factorial(int n) {
		if(n==0) {
			return 1;
		}
		else {
			return n*factorial(n-1);  
		}
		
		
		
	}
}

//재귀함수를 이용하는 문제!