namespace std {
#include <math.h>

int isinf(float x);
int isinf(double x);
int isinf(long double x);
bool isfinite(float x);
bool isfinite(double x);
bool isfinite(long double x);
bool isnan(float x);
bool isnan(double x);
bool isnan(long double x);
bool isnormal(float x);
bool isnormal(double x);
bool isnormal(long double x);
int fpclassify(float x);
int fpclassify(double x);
int fpclassify(long double x);
}