关键字总结

关键字

1. 结构体的名字就是首地址地址，且结构体的存储方式是尽可能紧凑，大小向结构体里最大字节对齐。

#include <stdio.h>

int main()
{
    int i;
    char j;
    struct person{
        int i;
        char str[2];
    };
    struct person lihua = {6, "a"};
    printf("int size = %d\r\n", sizeof(i));
    printf("char size = %d\r\n", sizeof(j));
    printf("person size = %d\r\n", sizeof(lihua));
    return 0;
}

输出

int size = 4
char size = 1
person size = 8

int 的字节最大
4+2=6,向四字节对齐，变成了8.
2. 结构体指针移动。

#include <stdio.h>

int main()
{
    struct person{
        int i;
        char sr;
        char str[2];
    };
    struct person *p;
    struct person lihua = {6, 'a', "cc"};
    p = &lihua;
    printf("befor = %p %p\r\n", &lihua, p);
    p = p + 4;
    printf("after = %p %p\r\n", &(lihua.sr), p);
    return 0;
}

输出

befor = 000000000061FE10 000000000061FE10
after = 000000000061FE14 000000000061FE30

061FE10
after = 000000000061FE14 000000000061FE30

指针移动了4*7个字节，4*sizeof（struct person）。