###
Given the first few factorials:

1! = 1

2! = 2 x 1 = 2

3! = 3 x 2 x 1 = 6

4! = 4 x 3 x 2 x 1 = 24

What is the sum of the first 15 factorials, NOT INCLUDING 0!?

**Language C++ :**

```
#include<iostream>
using namespace std;
class fact {
private:
unsigned long long int num,sum;
public:
fact() {
num = 0;
sum = 0;
}
void fact1() {
int i;
for(i = 1 ; i <= 15 ; i++) {
sum = sum + factorial_finder(i);
}
cout<<"Sum of first 15 factorials is = "<<sum<<endl;
}
long long int factorial_finder(int val) {
unsigned long long int i,f = 1;
for (i = 1 ; i <= val ; i++) {
f = f*i;
}
return(f);
}
};
int main() {
fact obj;
obj.fact1();
return(0);
}
```

###
**Output: **

**1401602636313**

**Unsigned long long long int is of**

**8 Bytes (64 Bits)**

Environment used to run this program :

- Gcc compiler
- Ubuntu 11.10 (Linux)
- vim editor