Double: double precision, floating point type, actually used to represent numbers with decimals, such as 5.5555;
Int: plastic, no decimal point, only 5, no 5.0;
String: String type, usually declared in double quotation marks, such as "Hello You!" .
However, this kind of thing should be explained in detail in textbooks.
He called the hospital again, and the doctor told him that Hao Meichen didn't go to the hospital all day. A sense of foreboding flooded Hao's mind. At 4 o'clock in the af