结构体对齐和深拷贝浅拷贝

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-------------------结构体对齐-----------------------

#include<stdio.h>#include<stdlib.h>struct info{//结构体变量的大小能够被其最宽基本类型成员的大小锁整除//22  同类型不需要加在一起short sh1; //2   最宽基本类型char sh2;  //1char ch[19];//19+1//28short sh3;//2+2   2，不足  补2int sh4;  //4   最宽基本类型char ch1[19];//19+1};void main1(){printf("%d", sizeof(struct info));getchar();}struct info1{short sh1;  //2+2int sh2;    //4char ch[19];//19+1  结构体数组不算基本类型};void main2(){struct info1 info11 = { 10,200,"123456" };printf("%p\n", &info11);    //00AFF980printf("%p\n", &info11.sh1);//00AFF980printf("%p\n", &info11.sh2);//00AFF984printf("%p\n", &info11.ch); //00AFF988getchar();}

--------------------深拷贝浅拷贝--------------------------

#define _CRT_SECURE_NO_WARNINGS#include<stdio.h>#include<stdlib.h>#include<string.h>struct string{char *p;int length;};void mainA()//浅拷贝，共用一片内存{struct string str1;str1.length = 10;str1.p = (char*)malloc(sizeof(char) * 10);strcpy(str1.p, "hello");//拷贝字符串到str1.p中printf("%s\n", str1.p);struct string str2;str2.length = str1.length;str2.p = str1.p;*(str1.p) = 'q';printf("str1=%s\n", str1.p);//qelloprintf("str2=%s\n", str2.p);//qello//浅拷贝，共用一片内存getchar();}void main()//深拷贝，互不干涉{struct string str1;str1.length = 10;str1.p = (char*)malloc(sizeof(char) * 10);strcpy(str1.p, "hello");//拷贝字符串到str1.p中printf("%s\n", str1.p);struct string str2;str2.length = str1.length;str2.p = (char*)malloc(sizeof(char) * 10);//单独开辟内存strcpy(str2.p, str1.p);//str1.p拷贝到str2.p*(str1.p) = 'q';printf("str1=%s\n", str1.p);//qelloprintf("str2=%s\n", str2.p);//hellogetchar();}

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