Double precision floating point

Float-single precision floating point

Int refers to an integer variable. The basic type for storing integer values is int, which is represented as a 32-bit integer in a 32-bit device and a 64-bit integer in a 64-bit device.

Float and Double refer to decimal variables, Float is a 32-bit value and Double is a 64-bit value. When using decimal, the compiler always infers it as a Double type, not a Float type. Therefore, if 64-bit precision is not required, you need to declare the variable as Float.

Int byte 4? Numerical range:-2147483648 ~+2147483647.

The value range of floating-point byte 4 is 3.4×10-38 ~ 3.4×10 38 (one decimal place).

The numerical range of double-byte 8 is1.7×10-308 ~1.7×10 308 (2 decimal places).