Defined in header <math.h>

Defined in header <math.h>

Defined in header <ctype.h>

Defined in header <wchar.h>

Defined in header <math.h>

Defined in header <threads.h>

Defined in header <stdio.h>

Defined in header <string.h>

Defined in header <complex.h>

A function declaration introduces an identifier that designates a function