//栈的顺序存储
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAXSIZE 1024

//栈的结构体
struct SStack
{   
    //将数组头作为栈尾，因为如果作为栈顶的话来回出入元素时间开销比较大
    void *data[MAXSIZE]; //数组
    int size;
};

typedef void * sstack;

//初始化栈
sstack init_stack(){
    struct SStack * myStack = malloc(sizeof(struct SStack));
    if (myStack==NULL)
    {
        return NULL;
    }
    memset(myStack->data,0,sizeof(void *)*MAXSIZE); //给数组赋初值0
    myStack->size=0; //初试化栈的大小
    return myStack;
}

//入栈
void push_stack(sstack stack,void *data ){
    if (stack==NULL)
    {
        return;
    }
    if (data==NULL)
    {
        return;
    }
    struct SStack *myStack=stack; //把用户传过来的指针转换成栈结构体指针

    //判断栈满
    if (myStack->size==MAXSIZE)
    {
        return;
    }
    
    //入栈就是尾插数组
    myStack->data[myStack->size]=data;
    myStack->size++;
}

//出栈
void pop_stack(sstack stack){
    if (stack==NULL)
    {
        return;
    }
    struct SStack *myStack=stack;

    //判断栈空
    if (myStack->size==0)
    {
        return;
    }
    
    //出栈其实就是尾删
    myStack->data[myStack->size-1]=NULL;
    myStack->size--;
}

//返回栈顶
void * top_stack(sstack stack)
{
	if (stack == NULL)
	{
		return NULL;
	}

	struct SStack * mystack = stack;

	if (mystack->size == 0)
	{
		return NULL;
	}
	return mystack->data[mystack->size - 1];
}

//判断栈是否为空
int isempty_stack(sstack stack){
    if (stack==NULL)
    {
        return -1; //返回-1代表栈空
    }
    struct SStack *myStack=stack;
    if (myStack->size==0)
    {
        return -1;
    }
    return 0;
}

//返回栈大小
int size_stack(sstack stack){
    if (stack==NULL)
    {
        return -1;
    }
    struct SStack *myStack=stack;
    return myStack->size;
}

//销毁栈
void destroy_stack(sstack stack){
    if (stack==NULL)
    {
        return;
    }    
    free(stack);
    stack=NULL;
}





//测试
struct Person
{
	char name[64];
	int age;
};

void test01(){
    //初始化栈
    sstack myStack=init_stack();
    //创建数据
	struct Person p1 = {  "aaa", 10 };
	struct Person p2 = {  "bbb", 20 };
	struct Person p3 = {  "ccc", 30 };
	struct Person p4 = {  "ddd", 40 };
	struct Person p5 = {  "eee", 50 };
    //入栈
	push_stack(myStack, &p1);
	push_stack(myStack, &p2);
	push_stack(myStack, &p3);
	push_stack(myStack, &p4);
	push_stack(myStack, &p5);
    
    printf("栈的元素个数为：%d\n", size_stack(myStack));

    while (isempty_stack(myStack)==0) //当栈不空时，元素依次出栈
    {
        struct Person *p=top_stack(myStack);
        printf("姓名：%s，年龄：%d\n",p->name,p->age);

        //元素出栈
        pop_stack(myStack);
    }
    
    //销毁栈
    destroy_stack(myStack);

}
int main()
{   
    test01();
    return 0;
}