Question

This is probably just an inconsistency of notation at cplusplus.com, but is there a difference between “long int” and “long” types in C++? cplusplus.com says that abs takes inputs of types “int” and “long”, whereas labs uses “long int”. I assume that this is basically a typo. If so, then is the only difference between abs and labs that labs is guaranteed to return a long?

Answer 1

There is no difference between long and long int.

The reason we have abs(long) and labs(long) (while both are equivalent) is that labs() is a remnant of the C library. C doesn’t have function overloading, so function abs() can only take one type (int) and the long one has to be called differently, hence labs.