练习 栈

参考 http://blog.youkuaiyun.com/liujiuxiaoshitou/article/details/53394888

#include<iostream>
#include<stdlib.h>
#include<stdio.h>
#include<math.h>
#define    ERROR 0
#define   OK 1
#define   STACK_INIT_SIZE 2
#define   STACKINCREMENT 1
#define    OVERFLOW   -2

typedef int Status;
typedef int SElemType;

using namespace std;

typedef struct
{

    SElemType *top;    //栈顶指针
    SElemType *base;   // 栈底指针
    int stacksize;      //栈大小


} SqStack;
//构造栈
Status initStack(SqStack &S)
{
    S.base=(SElemType * )malloc
           (STACK_INIT_SIZE*sizeof(SElemType));     //分配STACK_INIT_SIZE*SElemType大小空间
    //并且把首地址返回给S.base
    if(!S.base)                  //   x=0   !x=1
        exit(OVERFLOW);
    S.top=S.base;
    S.stacksize=STACK_INIT_SIZE;

    return OK;
}
//销毁栈
Status DestoryStack(SqStack &S)
{
    S.top=NULL;
    S.stacksize=0;
    free(S.base);               //释放空间
    S.base=NULL;                //将base=NULL防止出现野指针
    return OK;
}
//栈顶插入
void   Push(SqStack &S)
{    int e;
   int q=STACK_INIT_SIZE;
   int p=STACKINCREMENT;
    while(cin>>e)
    {
     if(S.top-S.base>= q)
    {
        S.base=(SElemType *)realloc(S.base,(S.stacksize+p)*sizeof(SElemType));
        S.top=S.base+q;
        S.stacksize=S.stacksize+q;
       q=q+p;

    }

    S.top++;
   *(S.top-1)=e;

    }cin>>e;

}
//遍历栈
Status StackTraverse(SqStack S)
{
    if(S.base ==NULL)
        return ERROR;
    if(S.top==S.base)
        cout<<"栈中无元素"<<endl;
    SElemType *p;
    p=S.top;

    while(p>S.base)
    {
        p--;
        cout<<*p;
    }
    return   OK;
}
Status StackOutput(SqStack S)
{
    SElemType *head;
    head=S.base;
    while(S.base!=S.top)
    {
       cout<<*(S.base);
       S.base++;
    }S.base=head;
}
int main()
{


    SqStack  S;
   initStack(S);
    Push(S); StackOutput(S);
    //StackTraverse(S);



}