I - u Calculate e

Description

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.        

Output

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.        

Sample Output

n e - -----------

0 1

1 2

2 2.5

3 2.666666667

4 2.708333333

#include<iostream>
#include<iomanip>
using namespace std;
double f(int n)
{
    long double a=;
    for(int i=;i<=n;i++)a*=i;
    return a;
}
int main()
{
    cout << "n e"<<endl<<"- -----------"<<endl;
    double e=;
    cout<<<<" "<<e<<endl;
    for(int i=;i<=;++i)
    {
        e+=/f(i);
        cout<<i<<" ";
        if(i!=)  cout<<setprecision()<<e<<endl;
        else cout<<setprecision()<<e<<<<endl;
    }
    //system("pause");
    return ;
}

不难！！不要忘了long double !!!!