03链栈_LinkStack--(栈与队列)

#include "stdio.h"    

#include "stdlib.h"   

#include "io.h"  

#include "math.h"  

#include "time.h"



#define OK 1

#define ERROR 0

#define TRUE 1

#define FALSE 0

#define MAXSIZE 20 /* 存储空间初始分配量 */



typedef int Status; 

typedef int SElemType; /* SElemType类型根据实际情况而定，这里假设为int */





/* 链栈结构 */

typedef struct StackNode

{

        SElemType data;

        struct StackNode *next;

}StackNode,*LinkStackPtr;





typedef struct

{

        LinkStackPtr top;

        int count;

}LinkStack;



Status visit(SElemType c)

{

        printf("%d ",c);

        return OK;

}



/*  构造一个空栈S */

Status InitStack(LinkStack *S)

{ 

        S->top = (LinkStackPtr)malloc(sizeof(StackNode));

        if(!S->top)

                return ERROR;

        S->top=NULL;

        S->count=0;

        return OK;

}



/* 把S置为空栈 */

Status ClearStack(LinkStack *S)

{ 

        LinkStackPtr p,q;

        p=S->top;

        while(p)

        {  

                q=p;

                p=p->next;

                free(q);

        } 

        S->count=0;

        return OK;

}



/* 若栈S为空栈，则返回TRUE，否则返回FALSE */

Status StackEmpty(LinkStack S)

{ 

        if (S.count==0)

                return TRUE;

        else

                return FALSE;

}



/* 返回S的元素个数，即栈的长度 */

int StackLength(LinkStack S)

{ 

        return S.count;

}



/* 若栈不空，则用e返回S的栈顶元素，并返回OK；否则返回ERROR */

Status GetTop(LinkStack S,SElemType *e)

{

        if (S.top==NULL)

                return ERROR;

        else

                *e=S.top->data;

        return OK;

}



/* 插入元素e为新的栈顶元素 */

Status Push(LinkStack *S,SElemType e)

{

        LinkStackPtr s=(LinkStackPtr)malloc(sizeof(StackNode)); 

        s->data=e; 

        s->next=S->top;    /* 把当前的栈顶元素赋值给新结点的直接后继，见图中① */

        S->top=s;         /* 将新的结点s赋值给栈顶指针，见图中② */

        S->count++;

        return OK;

}



/* 若栈不空，则删除S的栈顶元素，用e返回其值，并返回OK；否则返回ERROR */

Status Pop(LinkStack *S,SElemType *e)

{ 

        LinkStackPtr p;

        if(StackEmpty(*S))

                return ERROR;

        *e=S->top->data;

        p=S->top;                    /* 将栈顶结点赋值给p，见图中③ */

        S->top=S->top->next;    /* 使得栈顶指针下移一位，指向后一结点，见图中④ */

        free(p);                    /* 释放结点p */        

        S->count--;

        return OK;

}



Status StackTraverse(LinkStack S)

{

        LinkStackPtr p;

        p=S.top;

        while(p)

        {

                 visit(p->data);

                 p=p->next;

        }

        printf("\n");

        return OK;

}



int main()

{

        int j;

        LinkStack s;

        int e;

        if(InitStack(&s)==OK)

                for(j=1;j<=10;j++)

                        Push(&s,j);

        printf("栈中元素依次为：");

        StackTraverse(s);

        Pop(&s,&e);

        printf("弹出的栈顶元素 e=%d\n",e);

        printf("栈空否：%d(1:空 0:否)\n",StackEmpty(s));

        GetTop(s,&e);

        printf("栈顶元素 e=%d 栈的长度为%d\n",e,StackLength(s));

        ClearStack(&s);

        printf("清空栈后，栈空否：%d(1:空 0:否)\n",StackEmpty(s));

        return 0;

}