例如，常数oxffffffffl是一个有符号的long类型。

For example, the constant OxFFFFFFFFL is a signed long.

youdao

宇宙基本常数，比如电磁力强度之类的精细结构常数，符号位“ alpha ”，它们因为被假定为不变量而得名。

Fundamental constants such as the strength of the electromagnetic force - the so-called fine-structure constant, or alpha - get their name from the fact that they are supposedly the same everywhere.

youdao

如果我们希望所有位全部置位，那么一种可移植的方法是定义一个有符号的常数，其值为- 1。

If you want to turn all the bits on, a portable way to do this is to define a signed long constant with a value of -1.

youdao