java實現計算一個數的階乘

程式碼如下
import java.util.Scanner;
public class Calculate {
public static void main(String[] args) {
// TODO Auto-generated method stub
long sum=1;
System.out.println("請輸入要計算階乘的正整數：");
Scanner sc=new Scanner(System.in);
int b=sc.nextInt();
for (int i=1; i<=b; i++) {
sum *=i;
}
System.out.println("該數的階乘為："+sum);
}
}