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


public class Factorial {
    public static void main(String args[]) throws IOException {
        System.out.println("Please Input Any Number");
        int num = 0;
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String data = (String) br.readLine();

        num = Integer.parseInt(data);

        int result = num;
        for (int i = 1; i < num; i++) {
            result *= i;
            //result = result * i;
        }
        System.out.println(result);
    }

 }

Output

Input Any Number
5
120

Description:- In the above example find out the factorial of a number. Here, we have used BufferedReader class to input a number to find its factorial. The method readLine() of this class reads the value. As this method returns string type so we have converted it to integer. Then using the loop, we got the factorial of the input number.