#include<stdio.h>
#include<malloc.h>
#define STACK_INIT_SIZE 1
#define STACKINCREMENT 10
typedef char ElemType;
struct SqStack
{
     ElemType *elem;
     ElemType   *top;
     int stacksize;
};
int InitStack(struct SqStack *S)
{
     S->elem=(ElemType *)malloc(STACK_INIT_SIZE * sizeof(ElemType));
     if(!S->elem)
     {
         printf("初始化栈失败"); 
         return 0;
     }
     else
     {
         S->top=S->elem;
         S->stacksize= STACK_INIT_SIZE;
         printf("初始化栈成功\n");
         return 1;
     }
}
int Push(struct SqStack *S,ElemType x)
{
      if(S->top-S->elem>=S->stacksize)
      {
         S->elem=(ElemType *)realloc(S->elem,(S->stacksize+STACKINCREMENT) * sizeof(ElemType));
         if(!S->elem)
         {      printf("开辟空间失败\n");
              return 0;
         }
          else
          {
             S->top=S->elem+S->stacksize;
             S->stacksize+=STACKINCREMENT;
          }
     }
     *S->top=x;
     S->top++;
     return x;
}
int Pop(struct SqStack *S,ElemType x)
{
     if(S->top==S->elem)
     {
         printf("栈空\n");
         return 0;
     }
     else
     {   
         S->top--;
         x=*S->top;
         return x;
     }
}
int GetTop(struct SqStack *S,ElemType x)
{
     if(S->top==S->elem)
     {
         printf("栈空\n");

7楼

         return 0;
     }
     else
     {
         x=*(S->top-1);

         return x;
     }
}
int StackLength(struct SqStack *S)
{
     int n;
     n=S->top-S->elem;
     return(n);
}
void StackEmpty(struct SqStack *S)
{
     if(S->top==S->elem)
    
         printf("栈为空\n");
     else
         printf("栈不为空\n");
}
int VisitStack(struct SqStack *S)
{
     int k=0;
     while(S->top!=S->elem)
     {
         --S->top;
         k++;
         printf("%c ",*S->top);
     }
         S->top+=k;
         return 1;
}
int ClearStack(struct SqStack *S)
{
   if(S->top==S->elem)
       return 0;
   else
   {   S->top=S->elem;
      return 1;
   }

}
int DestoryStack(struct SqStack *S)
{
     free(S->elem);
     S->elem=NULL;
     S->top=NULL;
     S->stacksize=0;
     return 1;
}

void main()
{     int y;
     struct SqStack A;
     ElemType x=0;
     ElemType e;
     int cmd;
     printf("*******************************************************************************\n");
     printf("1－初始化栈      2－进栈         3－取栈顶元素       4－求栈长     5－销毁栈\n");
     printf("6－判空          7－遍历栈       8－出栈             9－清空栈     0-退出\n");
     printf("*******************************************************************************\n");
  
do{     printf("enter your choice ");
     scanf("%d",&cmd);
      e=getchar();
     switch(cmd)
     {