What are 4 valid variable types in C plus plus?

long, short, char and bool are 4 valid variable types. There are many more available, including (but not limited to) float, double, int, wchar_t, size_t, as well as compound types (such as long long) and unsigned/signed variations, such as unsigned int. All of these types are primitive, integral or built-in data types. More complex data types can be formed from struct, class and union declarations, but they all simply build upon the integral types.