package gudu;
public class Example3
{
public static void main(String[] args) {
int i=1,j=1,mut=1,sum=0;
for(;i<=20;i++)
{
for(;j<=i;j++)
{
mut=mut*j;
}
sum+=mut;
}
System.out.println("1!+2!+...+20!="+sum);
}
}
另一种方法:
package gudu;
public class Example3
{
public static void main(String[] args)
{
int i=1,sum=0,t=1;
while(i<21)
{
sum+=t;
i++;
t=t*i;
}
System.out.println("1!+2!+...+20!="+sum);
}
}