Include:
Prototype: int abs(int x);
double fabs(double x);
long labs(long x);
Returns: the absolute value of x.
See also: cabs
These functions return the absolute value of their argument x. The
functions and their return types are listed below:
Function Argument/Returns
abs integer value
fabs floating-point value
labs long integer value
Return Value
The return values for these functions are described above. There is no
error return.