#include <math.h>float roundf(float arg);double round(double arg); long double roundl(long double arg);
round( ), roundf( ), and roundl( ) were added by C99.
The round( ) family of functions returns the value of arg rounded to the nearest integer. However, the number is returned as a floating-point value. Values precisely between two values, such as 3.5, are rounded up.
Related functions are lround( ) and llround( ).