Fact

#include"stdafx.h"
#include "string"
#include <iostream>
using namespace std;
int main()
{
    int i;
    float f = 1, n, e = 1;
    cout << "Enter N : ";
    cin >> n;
    for (i = 1;i <= n;i++) {
        f = f*i;
        e += 1 / f;
    }
    cout << "E : " << e << endl;
    return 0;
}