#include "pch.h"
#include <iostream>
#include<Windows.h>
#include<string>
using namespace std;
#define OK    1
#define ERROR 0
#define OVER  -2
#define MAXSIZE 100
typedef int Status;   //返回状态
//顺序表结构体
struct SqStack
{
  char *base;
  char *top;
  int StackSize;
};
//初始化顺序栈
Status InitStack(SqStack &S)
{
  S.base = new char[MAXSIZE];
  if (!S.base)
  {
    Sleep(3000);
    exit(OVER);
  }
  S.top = S.base;
  S.StackSize = MAXSIZE;
  return OK;
}
//入栈
Status Push(SqStack &s, char &e)
{
  if (s.top - s.base == s.StackSize)
  {
    return ERROR;
  }
  *(s.top) = e;     //元素入栈，栈顶指针+1
  s.top++;
  return OK;
}
//出栈
Status Pop(SqStack &s, char &e)
{
  if (s.base == s.top)
  {
    return ERROR;
  }
  e = *(s.top - 1);   //这是出栈元素
  s.top--;
  return OK;
}
//得到栈顶元素
char GetTop(SqStack &s)
{
  if (s.top != s.base)
  {
    return *(s.top - 1);
  }
}
//打印栈元素
void PrintStack(SqStack &s)
{
  if (s.top != s.base)
  {
    cout << "栈的元素为：";
    int k = 0;
    for (int i = (s.top - s.base); i > 0; i--)
    {
      cout << *(s.top - 1) << "  ";
      --s.top;
      k++;
    }
    for (int j = 0; j <k; j++)
    {
      ++s.top;
    }
  }
}
int main()
{
  SqStack s;
  InitStack(s);
  int n;
  cout << "请输入初始个数：";
  cin >> n;
  cout << "请输入元素：" << endl;
  for (int i = 0; i < n; i++)
  {
    char p;
    cin >> p;
    Push(s, p);
  }
  PrintStack(s);
  cout << "栈顶为：" << GetTop(s) << endl;
  char p1;
  Pop(s, p1);
  cout << "出栈后";
  PrintStack(s);
  return 0;
}

#include "pch.h"
#include <iostream>
#include<string>
#include<Windows.h>
using namespace std;
#define OK    1
#define ERROR 0
#define OVER  -2
#define MAXSIZE 100
typedef int Status;   //返回状态
typedef struct StackNode
{
  char date;
  StackNode *next;
}*LinkStack;
//初始化链栈
Status InitStack(LinkStack s)
{
  s = NULL;
  return OK;
}
//入栈
Status Push(LinkStack s, char e)
{
  LinkStack p;
  p = new StackNode;
  p->date = e;
  p->next = s;
  s = p;
  return OK;
}
//出栈
Status Pop(LinkStack s, char &e)
{
  LinkStack p;
  if (s == NULL)
  {
    return ERROR;
  }
  e = s->date;
  p = s;        //用p临时保存栈顶元素的值
  s = s->next;    //修改栈顶指针
  delete p;
  return OK;
}
//取栈顶元素的值
char Getchar(LinkStack s)
{
  if (s!=NULL)
  {
    return s->date;
  }
  cout << "栈为空，无法取栈顶元素！" << endl;
  return ERROR;
}
int main()
{
  StackNode s;
  InitStack(&s);
  char a, b, c;
  a = 'c', b = 'b', c = 'a';
  Push(&s, a);
  Push(&s, b);
  Push(&s, c);
  cout << "出栈前栈顶为：";
  Getchar(&s);
  char e;
  Pop(&s,e);
  cout << "出栈后栈顶为：";
  return 0;
}