¹⁷Notice that the C++ standard states that the value representation of floating-point types is implementation-defined. The C standard requires that the type double provides at least as much precision as float, and the type long double provides at least as much precision as double. The gcc 5.4 version that we are using in this book represents float using 4 bytes and double with 8, but you should check whether this is true with the compiler that you are using.