# simple calculator

Bjarne Stroustrup “Programming Principles and Practice Using C++”
Chapter 4 Exercise 5
Using std_lib_facilities.h by Bjarne Stroustrup.

[code language=”cpp”]
// Philipp Siedler
// Bjarne Stroustrup’s PP
// Chapter 4 Exercise 5

#include "std_lib_facilities.h"

int main() {

double value1 = 0.0;
double value2 = 0.0;
char operat = ‘ ‘;

cout << "Please enter two double values and an operator in a row with space in between.\n";

while (cin >> value1 >> value2 >> operat)
{
if (operat == ‘+’)
{
cout << value1 << " " << operat << " " << value2 << " equals to: " << value1 + value2 << "\n";
}
if (operat == ‘-‘)
{
cout << value1 << " " << operat << " " << value2 << " equals to: " << value1 – value2 << "\n";
}
if (operat == ‘/’)
{
cout << value1 << " " << operat << " " << value2 << " equals to: " << value1 / value2 << "\n";
}
if (operat == ‘*’)
{
cout << value1 << " " << operat << " " << value2 << " equals to: " << value1 * value2 << "\n";
}
}
return 0;

keep_window_open("-");
}
[/code]

```Output:
Please enter two double values and an operator in a row with space in between.
6.3 8.9 *
6.3 * 8.9 equals to: 56.07```