Learning bit segment (1)

1. What is a bit segment ？

The declaration and structure of a bit segment are similar , There are two differences ：

1. The member of the segment must be int、unsigned int or signed int .

2. There is a colon and an Arabic numeral after the member name of the bit field .

for example ：

struct  A

{              int   a: 2;

               int   b: 5;

               int   c: 10;

               int   d: 30;

};

A It's a bit segment type .

that A What is the size of ？

If there is no number after the colon, we can get the result by calculating the structure 16, What is this size ？

 

 

  We can find that there are only eight bytes , Then we can know that the units of this number are bit.