C语言 结构体、结构体变量和结构体指针

执行结果截图：

 

 代码：

#include "stdio.h"
#include "stdlib.h"

# define PRINTF(templt, ...) fprintf(stderr, templt, ##__VA_ARGS__)
# define PRINT(format, ...) printf(# format, ##__VA_ARGS__)

// 定义一个宏，求两个内存单元地址之间的距离
# define ABS(x, y) (((long long int)x - (long long int)y) > 0 ? ((long long int)x - (long long int)y) : - ((long long int)x - (long long int)y))

struct Date
{
    int year;
    int month;
    int day;
} date;

struct Book
{
    char title[120];
    char author[40];
    float price;
    struct Date date;
    char publisher[40];
} book = {
        "《陆王》",
        "威漫",
        9.87,
        2022,
        4,
        1,
        "山姆大叔出版社"
};

int main(void)
{
    // 定义一个结构体指针pt
    struct Book * pt;
    struct Book * pt1;
    struct Book * pt2;
    long long int addrDistance;

    pt = &book;
    PRINTF("Addr of book ：%p\n", pt);

    PRINT(\n=====打印结构体book的变量值=====\n);
    PRINT(书名 ： %s\n, book.title);
    PRINT(作者 ： %s\n, book.author);
    PRINT(售价 ： %.2f\n, book.price);
    PRINT(出版日期 ： %d-%d-%d\n, book.date.year, book.date.month, book.date.day);
    PRINT(出版社 ： %s\n, book.publisher);

    /*
    // 输入结构体变量的值并打印
    PRINT(请输入书名 ：);
    scanf("%s", book.title);

    PRINT(请输入作者 ：);
    scanf("%s", book.author);

    PRINT(请输入售价 ：);
    scanf("%f", &book.price);

    PRINT(请输入出版日期（按年月日依次输入）：);
    scanf("%d", &book.date.year);
    scanf("%d", &book.date.month);
    scanf("%d", &book.date.day);

    PRINT(请输入出版社 ：);
    scanf("%s", book.publisher);

    PRINT(\n=====录入的数据为=====\n);
    PRINT(书名 ： %s\n, book.title);
    PRINT(作者 ： %s\n, book.author);
    PRINT(售价 ： %.2f\n, book.price);
    PRINT(出版日期 ： %d-%d-%d\n, book.date.year, book.date.month, book.date.day);
    PRINT(出版社 ： %s\n, book.publisher);
    */

    PRINT(\n=====对结构体变量进行初始化并直接打印其值=====\n);
    // 初始化一个结构体变量，可以不按结构体声明的成员顺序进行初始化：
    struct Book kungFuBible =
            {
                    .publisher = "功夫宝典出版社",
                    .title = "《葵花宝典》",
                    .author = "前朝太监",
                    .price = 999.99,
                    .date = {2012, 12 , 12}
            };

    PRINT(书名 ： %s\n, kungFuBible.title);
    PRINT(作者 ： %s\n, kungFuBible.author);
    PRINT(售价 ： %.2f\n, kungFuBible.price);
    PRINT(出版日期 ： %d-%d-%d\n, kungFuBible.date.year, kungFuBible.date.month, kungFuBible.date.day);
    PRINT(出版社 ： %s\n, kungFuBible.publisher);

    // 初始化一个结构体变量，可以不按结构体声明的成员顺序进行初始化：
    struct Book compBook =
            {
                    .publisher = "社会大学出版社",
                    .title = "《C语言-平凡之路》",
                    .author = "鲁有脚",
                    .price = 66.66,
                    .date = {2021, 5, 1}
            };

    PRINT(\n=====对结构体指针以*解引用打印结构体变量的值=====\n);
    pt1 = &compBook;
    PRINTF("pt1 pointed to &compBook : %p\n", pt1);
    PRINTF("Addr of compBook.title : %p which is %lld away from &compBook\n", &((* pt1).title), ABS(&((* pt1).title), pt1));
    PRINT((* pt1).title : %s\n, (* pt1).title);
    PRINTF("Addr of (* pt1).author : %p which is %lld away from &compBook\n", &((* pt1).author), ABS(&((* pt1).author), pt1));
    PRINT((* pt1).author : %s\n, (* pt1).author);
    PRINTF("Addr of (* pt1).price : %p which is %lld away from &compBook\n", &((* pt1).price), ABS(&((* pt1).price), pt1));
    PRINT((* pt1).price : %.2f\n, (* pt1).price);
    PRINTF("Addr of (* pt1).date.year : %p which is %lld away from &compBook\n", &((* pt1).date.year), ABS(&((* pt1).date.year), pt1));
    PRINT((* pt1).date : %d-%d-%d\n, (* pt1).date.year, (* pt1).date.month, (* pt1).date.day);
    PRINTF("Addr of (* pt1).publisher : %p which is %lld away from &compBook\n", &((* pt1).publisher), ABS(&((* pt1).publisher), pt1));
    PRINT((* pt1).publisher : %s\n, (* pt1).publisher);

    PRINT(\n=====用结构体指针指向结构体变量打印结构体变量的值=====\n);
    pt2 = &kungFuBible;
    PRINTF("pt2 pointed to  &kungFuBible: %p\n", pt2);
    PRINTF("Addr of kungFuBible.title : %p\n", &(pt2->title));
    PRINT(pt2 -> title : %s\n, pt2->title);
    PRINT(pt2 -> author : %s\n, pt2->author);
    PRINT(pt2 -> price : %.2f\n, pt2->price);
    PRINT(pt2 -> date : %d-%d-%d\n, pt2->date.year, pt2->date.month, pt2->date.day);
    PRINT(pt2 -> publisher : %s\n, pt2->publisher);

    PRINTF("\n=====结构体和结构体变量所占字节数=====\n");
    PRINTF("size of memory cell address : %d\n", sizeof(&book));
    PRINTF("size of (struct Book *) type : %d\n", sizeof(struct Book *));
    PRINTF("size of (struct Book) type : %d\n", sizeof(struct Book));
    PRINTF("size of kungFuBible : %d\n", sizeof(kungFuBible));
    PRINTF("size of kungFuBible.title : %d\n", sizeof(kungFuBible.title));
    PRINTF("size of kungFuBible.author : %d\n", sizeof(kungFuBible.author));
    PRINTF("size of kungFuBible.price : %d\n", sizeof(kungFuBible.price));
    PRINTF("size of kungFuBible.date : %d\n", sizeof(kungFuBible.date));
    PRINTF("size of kungFuBible.publisher : %d\n", sizeof(kungFuBible.publisher));

    PRINTF("Address distance of book and compBook are %lld bytes apart\n", ABS(&book, &compBook));
    PRINTF("Address distance of book and kungFuBible are %lld bytes apart\n", ABS(&book, &kungFuBible));
    PRINTF("Address distance of compBook and kungFuBible are %lld bytes apart\n", ABS(&compBook, &kungFuBible));

    return 0;
}