How much bytes have floating-point datatype n C++? For diffrent platform it may be differ number.

To do it You may use header file: `cfloat`

applies constant variables. It is example showsnumber of digits of in these datatypes. It use constants.

#include #include using namespace std; int main() { cout << "Number of decimal digits that can be rounded into a floating-point:\n" << endl; cout << "- float: " << FLT_DIG << endl; cout << "- double: " << DBL_DIG << endl; cout << "- long double: " << LDBL_DIG << endl; cout << "Floating-point number of bits in mantissa(decimal digits):\n" << endl; cout << "- float: " << FLT_MANT_DIG << endl; cout << "- double " << DBL_MANT_DIG << endl; cout << "- long double " << LDBL_MANT_DIG << endl; cout << "Minimum and maximum integer value for the exponent of a base-10 :\n" << endl; cout << "- float from " << FLT_MIN_10_EXP << " to " << FLT_MAX_10_EXP << endl; cout << "- double from " << DBL_MIN_10_EXP << " to " << DBL_MAX_10_EXP << endl; cout << "- double long from " << LDBL_MIN_10_EXP << " to " << LDBL_MAX_10_EXP << endl; return 0; }

And it is result of running this programm on Windows 7 64-bit: