Your variant is as correct as it ever gets. %lf is the correct format specifier for double. But it became so in C99. Before that one had to use %f.
float e double A diferença entre o float e o double é a precisão, ou seja, o quanto varia, o quanto consegue expressar um valor próximo do real, é o número de casas decimais que ele consegue suportar. Esses tipos são chamados de ponto flutuante binários.
Qual a forma correta de usar os tipos float, double e decimal?
El tamaño en memoria de cada uno de esos tipos es diferente. float ocupa 32 bits mientras que double ocupa 64 bits. Esto afecta a la cantidad de números diferentes que "caben" en cada uno de estos formatos. En double se pueden almacenar números más grandes y también más decimales. Con los números que has probado no se ve diferencia porque cout << redondea la representación interna para ...
A Double in Java is the class version of the double basic type - you can use doubles but, if you want to do something with them that requires them to be an object (such as put them in a collection), you'll need to box them up in a Double object.
Returning an empty or zero-length string (e.g. "") to make a cell appear blank is a common practise in a worksheet formula but recreating that option when inserting the formula through the Range.Formula or Range.FormulaR1C1 property in VBA is unwieldy due to the necessity of having to double-up the double-quote characters within a quoted string.
How to create a string or formula containing double quotes in Excel ...