#include<stdio.h>

#include<stdlib.h>

typedef struct

{

    char *base;

    char *top;

    int stacksize;

}sqStack;

//////////////////////////////////////

//创建一个栈

#define STACK_SIZE 100

void initstack(sqStack *stack )

{

    stack->base = (char*)malloc( STACK_SIZE * sizeof(char));

    if (!stack->base)

    {

        exit(0);

    }

    stack->top = stack->base;

    stack->stacksize = STACK_SIZE;

}

////////////////////////////////////

//入栈操作

#define STACK_MORE 10

void Push(sqStack *stack , char c)

{

    if (stack->top - stack->base > stack->stacksize)

    {

        stack->base = (char*)realloc(stack->base , (stack->stacksize + STACK_MORE) * sizeof(char));

        if (!stack->base)

        {

            exit(0);

        }

        stack->top = stack->base + stack->stacksize;

        stack->stacksize = stack->stacksize + STACK_MORE;

    }

    *(stack->top) = c;

    stack->top++;

}

//////////////////////////////////////

//出栈操作

void Pop(sqStack *stack , char *c)

{

    if (stack->base == stack->top)

    {

        return;

    }

    *c = *--(stack->top);

}

///////////////////////////////////////

//清空栈

void ClearStack(sqStack *stack)

{

    stack->top = stack->base;

}

//////////////////////////////////////

//销毁一个栈

void destoryStack(sqStack *stack)

{

    for (size_t i = 0; i < stack->stacksize; i++)

    {

        free(stack->base);

        stack->base++;

    }

    stack->base=stack->top = NULL;

    stack->stacksize = 0;

}

int main()

{

    sqStack stack;

    char c=1;

    printf("请安任意键创建一个栈...\n");

    getchar();

    initstack(&stack);

    printf("创建成功！\n");

    printf("请输入要压入栈的一个字符串(读取到0截至)： ");

    while ((c = getchar()) != '\n')

    {

        //scanf("%c",&c);

        //fflush(stdin);

        if (c!='\n')

        {

            Push(&stack , c);

        }

    }

    printf("压入字符完成，正在打印字符串...\n");

    for (size_t i = 0; i < (stack.top - stack.base); i++)

    {

        printf("%c",*(stack.base + i));

    }

    putchar('\n');

    printf("请输入要弹出几个字符：");

    int k;

    scanf("%d",&k);

    while (k)

    {

        k--;

        Pop(&stack , &c);

        printf("字符%c已弹出！\n",c);

    }

    printf("弹出字符完成，正在打印字符串...\n");

    for (size_t i = 0; i < (stack.top - stack.base); i++)

    {

        printf("%c",*(stack.base + i));

    }

    putchar('\n');

    printf("接下来你可以选择清空（输入1）或者销毁（输入2）这个栈:");

    scanf("%d",&k);

    fflush(stdin);

    switch (k)

    {

    case 1:

        ClearStack(&stack);

        if (stack.top == stack.base)

        {

            printf("清空完成！");

        }

        break;

    case 2:

        destoryStack(&stack);

        if(stack.base == NULL && stack.top == NULL && stack.stacksize == 0)

        {

            printf("已成功销毁！");

        }

        break;

    default:

        break;

    }

    return 0;

}