长路漫漫，唯剑作伴--基础

一、结构体

结构体定义

    struct stu{
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在学习小组
        float score;  //成绩
    }

结构体变量

struct stu stu1, stu2;

    struct stu{
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在学习小组
        float score;  //成绩
    } stu1, stu2;

    struct{  //没有写 stu
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在学习小组
        float score;  //成绩
    } stu1, stu2;

结构体访问

    #include <stdio.h>
    int main(){
        struct{
            char *name;  //姓名
            int num;  //学号
            int age;  //年龄
            char group;  //所在小组
            float score;  //成绩
        } stu1;
        //给结构体成员赋值
        stu1.name = "Tom";
        stu1.num = 12;
        stu1.age = 18;
        stu1.group = ‘A‘;
        stu1.score = 136.5;
        //读取结构体成员的值
        printf("%s的学号是%d，年龄是%d，在%c组，今年的成绩是%.1f！\n", stu1.name, stu1.num, stu1.age, stu1.group, stu1.score);
        return 0;
    }

结构体赋值

    struct{
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在小组
        float score;  //成绩
    } stu1, stu2 = { "Tom", 12, 18, ‘A‘, 136.5 };

二、结构体数组

    struct stu{
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在小组
        float score;  //成绩
    }class[5];

    struct stu{
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在小组
        float score;  //成绩
    }class[5] = {
        {"Li ping", 5, 18, ‘C‘, 145.0},
        {"Zhang ping", 4, 19, ‘A‘, 130.5},
        {"He fang", 1, 18, ‘A‘, 148.5},
        {"Cheng ling", 2, 17, ‘F‘, 139.0},
        {"Wang ming", 3, 17, ‘B‘, 144.5}
    };

    struct stu{
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在小组
        float score;  //成绩
    }class[] = {
        {"Li ping", 5, 18, ‘C‘, 145.0},
        {"Zhang ping", 4, 19, ‘A‘, 130.5},
        {"He fang", 1, 18, ‘A‘, 148.5},
        {"Cheng ling", 2, 17, ‘F‘, 139.0},
        {"Wang ming", 3, 17, ‘B‘, 144.5}
    };

三、结构体和指针

    struct stu{
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在小组
        float score;  //成绩
    } stu1 = { "Tom", 12, 18, ‘A‘, 136.5 };
    //结构体指针
    struct stu *pstu = &stu1;

    struct stu{
        char *name;  //姓名
        int num;  //学号
        int age;  //年龄
        char group;  //所在小组
        float score;  //成绩
    } stu1 = { "Tom", 12, 18, ‘A‘, 136.5 }, *pstu = &stu1;

    #include <stdio.h>
    int main(){
        struct{
            char *name;  //姓名
            int num;  //学号
            int age;  //年龄
            char group;  //所在小组
            float score;  //成绩
        } stu1 = { "Tom", 12, 18, ‘A‘, 136.5 }, *pstu = &stu1;
        //读取结构体成员的值
        printf("%s的学号是%d，年龄是%d，在%c组，今年的成绩是%.1f！\n", (*pstu).name, (*pstu).num, (*pstu).age, (*pstu).group, (*pstu).score);
        printf("%s的学号是%d，年龄是%d，在%c组，今年的成绩是%.1f！\n", pstu->name, pstu->num, pstu->age, pstu->group, pstu->score);
        return 0;
    }

四、枚举

    enum week{ Mon = 1, Tues, Wed, Thurs, Fri, Sat, Sun };
    enum week a = Mon, b = Wed, c = Sat;

五、C++结构体

     //定义一个结构体，类型为struct Student
2      struct  Student
3      {
4          string name;
5          double eng;
6          double ch;
7      };
8
9      //定义了一个结构体，类型为struct Student；且定义了一个结构体实例，名叫Stu
10      struct  Student
11      {
12          string name;
13          double eng;
14          double ch;
15      }Stu;
16
17      //定义了无名的结构体，且定义了一个结构体实例，名叫Stu
18      struct
19      {
20          string name;
21          double eng;
22          double ch;
23      }Stu;
24
25      //重定义结构体，类型为struct Student 或者是Stu
26      typedef struct  Student
27      {
28          string name;
29          double eng;
30          double ch;
31      }Stu;
32
33      //重定义结构体，类型为Stu
34      typedef struct
35      {
36          string name;
37          double eng;
38          double ch;
39      }Stu;