floor, floorf, floorl- round down floating point number

Syntax	#include <math.h> double floor(double x); float floorf(float x); long double floorl(long double);
Description	These functions round down the floating-point number x to an integer.
Return val.	Largest integer in floating-point format not greater than x.
Notes	The integral value returned by floor(), floorf(), or floorl() as a double, float or long might not be expressible as an int or long int. The return value should be tested before assigning it to an integer type to avoid the undefined results of an integer overflow.
See also	ceil(), ceilf(), ceill(), fabs(), math.h.