"Learning note", "C language" enumeration

First, the concept of enumerations

Enumerations are a basic data type in the C language, not a constructed type, which can be used to declare a set of constants. When a variable has several fixed possible values, the variable can be defined as an enumeration type. For example, you can use a variable of an enumeration type to represent the season, because there are only 4 possible values for the season: Spring, summer, autumn, and winter.
1. The general form is: Enum enumeration Name {Enumeration element 1, Enumeration element 2,......};

For example:
Enum Season {
Spring
Summer
Autumn
Winter
};

Second, the use of attention

The 1> C language compiler handles enumeration elements (spring, summer, and so on) As Integer constants, called enumeration constants.
The value of the 2> enumeration element depends on the order in which the enumeration elements are arranged when defined. By default, the first enumeration element has a value of 0, the second is 1, and sequentially adds 1.
Enum Season {Spring, summer, autumn, winter};
That is, spring has a value of 0,summer value of 1,autumn and a value of 2,winter is 3

3> can also change the value of an enumeration element when defining an enumeration type
Enum season {spring, summer=3, Autumn, winter};

An enumeration element with no value specified, with a value of 1 for the previous element. It is also said that the value of spring is 0,summer value of 3,autumn is 4,winter value is 5

1#include <stdio.h>2 3 intMain ()4 {5     enumSex {man, Woman, unkown};6     7     //0 Male 1 female-1 unspecified8     //int sex = 3;9     //enum Sex s = unkown;Ten      One     //1. Defining Enum Types A     enumSeason -     { -Spring =1, the Summer, - Autumn, - Winter -     }; +      -     //2. Defining enumeration Variables +     enumSeason s =100000; A      at      -printf"%d\n", s); -      -      -     return 0; -}

"Learning note", "C language" enumeration