How enum is used in C + + (GO)

Enum overview

Enum enum type is a type of data in C/s + +, which is a user-defined type like struct and class, which is characterized by the fact that the value of the enum type variable is limited and can be enumerated.

Enum definition

C + + Enum enumeration format:

Enum < enum type name > {< enumeration Table >};

Enum {< Enumeration table >}< variable Name table >;

The first C + + Enum enumeration value corresponds to an integer number, usually if the enumeration constant does not define a numeric value, then the first enumeration value corresponds to the constant value 0, and then increments, and if the first enumeration constant defines a value, then the value is incremented, with each constant separated by "," instead of ";", the last value does not use a symbol.

enum BOOL {false,true}; The bool type is a pre-defined enumeration of C + +

enum Example

2. #include < iostream.h>
6. void Main ()
8. ... {
10. Example 1
12. Enum Day ... {sun,mon,tue,wed,thu,fri,sat};//defines an enumeration of day
14. Day d = Sun;
    D can only be equal to one of "Sun,mon,tue,wed,thu,fri,sat", no other value!
16. cout< < "value is"< < D<   < Endl;
20. You can also define multiple variables
22. Enum Day ... {Sun,mon,tue,wed,thu,fri,sat};
24. Day d1,d2,d3;
26. D1 = Thu; d2 = Sat;  d3 = Tue;
27. cout <   <   "d1 && d2 && d3 " <   <   d1 <   <   " " <   <   d2<   <   " " <   <   d3<   <   Endl ;  
31. Example 2
33. Enum... {Sun,mon,tue,wed,thu,fri,sat} D;
35. D = Mon;
37. cout< < "value is"< < D<   < Endl;
41. Example 3
43. Enum...  {sun=10,mon,tue,wed,thu,fri,sat} d1,d2,d3,d4;
45. D1 = Sun; d2 = Mon; d3 = Tue;  d4 = Wed;
46. cout<<D1< < "< < D2< < " "<  < D3<   < ""< < D4< < Endl;
    Output ten
50. Example 4
52. Enum...  {sun=,mon=1,tue,wed,thu,fri,sat} d1,d2,d3,d4;
54. D1 = Sun; d2 = Mon; d3 = Tue;  d4 = Wed;
55. cout<<D1< < "< < D2< < " "<  < D3<   < ""< < D4< < Endl;
    Output 1 2 3
57. }

How enum is used in C + + (GO)