#include <iostream.h>
void main()
{
long double i, a=1 ,k;
double sum=0, x;

for(i=1;;i++)
{
a=1;
for(k=1;k<=i;k++)
{

a *=k;
}
cout<<a<<endl;
x= 1.0/a;
sum=sum+x;
if(x<=1e-108)
break;
}
cout<<sum;

}注e=1/1!+1/2!+3/3!......