1到20阶乘的和

public class JieCheng{
public static void main(String[] args){
int i=0;
double a=1;
double sum=0;
for(i=1;i<=20;i++){
a=a*i;
sum+=a;

}
System.out.println(sum);
}

}

转载于:https://www.cnblogs.com/140302528yuyue/p/5276980.html