hdoj1012--u Calculate e

[align=left]Problem Description[/align]
A simple mathematical formula for e is



where n is allowed to go to infinity.
This can actually yield very accurate approximations of e using relatively small
values of n.

[align=left]Output[/align]
Output the approximations of e generated by the above
formula for the values of n from 0 to 9. The beginning of your output should
appear similar to that shown below.
[align=left]Sample Output[/align]

n e

- -----------

0 1

1 2

2 2.5

3 2.666666667

4 2.708333333

#include<iostream>
#include <iomanip>

using namespace std;

int main()
{
int i,n;
double s,t;
cout<<"n e"<<endl;
cout<<"- -----------"<<endl;
cout<<"0 1"<<endl;
cout<<"1 2"<<endl;
cout<<"2 2.5"<<endl;
s=2.5;
n=2;
for(i=3; i<=9; i++)
{
n=i*n;
s+=1.0/n;
cout<<i<<" "<<fixed<<setprecision(9)<<s<<endl;
}
return 0;
}