嵌入式学习14（数据结构开篇：结构体，栈）

Talk is cheap,show me the code.
结构体

#include <stdio.h>struct student//定义一个新的类型（分配空间的模板）{    int id;    char name[10];    char addr[100];    short c_sore;};typedef struct student stu;//stu就是student的别名void main(){//基本用法    struct student a1;//定义变量，分配空间//  a1={17002,"123","456",100};  错误，只能在定义时初始化，或在之后逐一赋值    struct student a2={17002,"cmz","wuhan",100};//初始化    printf("%d",a2.id);//引用//指针    struct student *pst=&a2;    printf("%d\n",sizeof(pst));//4    printf("%d %s %s %d\n",pst->id,(*pst).name,pst->addr,(*pst).c_sore);//数组    stu e1702[10]={ {17001,"yha","wuhan",98},{17003,"hello","hankou",90},            {17001,"yha","wuhan",98},{17003,"hello","hankou",90},            {17001,"yha","wuhan",98},{17003,"hello","hankou",90},            {17001,"yha","wuhan",98},{17003,"hello","hankou",90},            {17007,"haha","iam",98},{17003,"hello","hankou",90}              };    int buf[10]={1,2,3,4,5,6,7,8,9,0};    printf("%s %d %s\n",e1702[0].name,e1702[0].id,e1702[0].addr);//下标法    printf("%s%d %s\n",(e1702+1)->name,(e1702+1)->id,(e1702+1)->addr);//指针//查找17007的个人信息，如果成功，则打印17007所有信息    int i,flag=0;    for(i=0;i<10;i++)    {        if(e1702[i].id==17007)        {               flag=1;                 printf("%d号学生的信息为：",e1702[1].id);          printf("%s %s %d\n",e1702[i].name,e1702[i].addr,e1702[i].c_sore);            break;//退出循环        }    }    if (flag==0)        printf("没有该学生的信息\n");}

注：分配空间时，会以字节对齐进行分配空间
1、 以最大类型长度作为单位分配空间
2、 如果此成员分配的空间足够供下一个成员使用，则共享此空间
struct student
{
int id; //4个
char name; //4个与后面共享
char addr;
short c;
};
//sizeof(struct student)为8

         ***栈***

头文件

#ifndef _STACK_DEF_#define _STACK_DEF_#define false 0#define true 1#define MAXSIZE 10typedef char BOOL;typedef int StackType;//模型：新的类型struct stack{    StackType buf[MAXSIZE];    int top;//指向栈顶元素};//一个容器extern BOOL initStack(struct stack*);//初始化extern BOOL isEmpty(struct stack*);//判断空extern BOOL isFull(struct stack*);//判断满extern BOOL push(struct stack*,StackType);//进栈extern BOOL pop(struct stack*,StackType*);//出栈#endif

主函数

#include"stack.h"#include<stdio.h>/********(1)初始化栈***********/BOOL initStack(struct stack* ps){    //初始化top值，指向空    ps->top=-1;     return true;}/******(2)判断是否为空******///返回值：空-true  非空-falseBOOL isEmpty(struct stack* ps){    //左值尽可能为常量（在等于运算符中）    if(-1==ps->top)    {        return true;    }    return false;}/*******(3)是否为满********/BOOL isFull(struct stack* ps){    if(MAXSIZE-1==ps->top)        return true;    else        return false;}/******(4)压栈*********///前提：不能为满BOOL push(struct stack* ps,StackType data){    if(isFull(ps))//判断为满        return false;//压栈失败    ps->buf[ ++(ps->top) ]=data;//前自加：先自加，再取值    return true;//压栈成功}/******（5）出栈*******///前提：不能为空BOOL pop(struct stack* ps,StackType* pdata){    if(isEmpty(ps))        return false;    //取出栈顶    *pdata=ps->buf[  ps->top-- ];   //后自减：先取值，后自减    //出栈成功    return true;}void main(){    struct stack s;    initStack(&s);    push(&s,1);    push(&s,2);    push(&s,3);    StackType data;    while(pop(&s,&data))    {        printf("%d",data);    }    putchar(10);//换行}