Need help with the C++ programming. I am trying to compute the count of values, the average, and the standard deviation of the input given by user. My output is correct except for the standard deviation. My code is below:

Thanks

```
#include <iostream>
#include <string>
#include <cmath>
using namespace std;
int main()
{
bool more = true;
int count = 0;
double sum = 0;
cout << " Enter a value: (CTRL-D to quit): ";
float num = 0.0;
cin >> num;
while (true)
{
++count;
cout << count << endl;
sum += num;
cout << " Enter a value: (CTRL-D to quit): ";
cin >> num;
if (cin.eof())
{
break;
}
}
double avg = 0;
avg = sum / count;
double s_dev = 0;
s_dev = sqrt( (( pow(sum,2.0)) -(( 1.0/count) * (pow(sum,2.0))))/ (count -1.0));
cout << endl << endl;
cout << " There are " << count << " values. " << endl;
cout << " The average is: " << avg << endl;
cout << " The standard deviation is: " << s_dev << endl;
return 0;
}
```

<< moderator edit: added code tags: [code][/code] >>