数据结构-链式栈的实现

#ifndef Stack_H
#define Stack_H

typedef int Item;
typedef struct node * PNode;
/*定义栈节点类型*/
typedef struct node
{
Item data;
PNode down;
}Node;
/*定义栈类型*/
typedef struct stack
{
PNode top;
int size;
}Stack;
/*构造一个空栈*/
Stack *InitStack();

/*销毁一个栈*/
void DestroyStack(Stack *ps);

/*把栈置空*/
void ClearStack(Stack *ps);

/*判定是否为空栈*/
int IsEmpty(Stack *ps);

/*返回栈大小*/
int GetSize(Stack *ps);

/*返回栈顶元素*/
PNode GetTop(Stack *ps,Item *pitem);

/*元素入栈*/
PNode Push(Stack *ps,Item item);

/*元素出栈*/
PNode Pop(Stack *ps,Item *pitem);

/*遍历栈并访问visit函数*/
void StackTraverse(Stack *ps,void (*visit)());

#endif

#include"Stack.h"
#include<malloc.h>
#include<stdlib.h>
/*构造一个空栈*/
Stack *InitStack()
{
Stack *ps = (Stack *)malloc(sizeof(Stack));
if(ps!=NULL)
{
ps->top = NULL;
ps->size = 0;
}
return ps;
}

/*判定是否为空栈*/
int IsEmpty(Stack *ps)
{
if(ps->top == NULL && ps->size == 0)
return 1;
else
return 0;
}

/*返回栈大小*/
int GetSize(Stack *ps)
{
return ps->size;
}

/*元素入栈*/
PNode Push(Stack *ps,Item item)
{
PNode pnode = (PNode)malloc(sizeof(Node));
if(pnode != NULL)
{
pnode->data = item;
pnode->down = GetTop(ps,NULL);
ps->size++;
ps->top = pnode;

}
return pnode;
}

/*返回栈顶元素*/
PNode GetTop(Stack *ps,Item *pitem)
{
if(IsEmpty(ps)!=1&&pitem!=NULL)
{
*pitem = ps->top->data;
}
return ps->top;
}

/*元素出栈*/
PNode Pop(Stack *ps,Item *pitem)
{
PNode p = ps->top;
if(IsEmpty(ps)!=1&&p!=NULL)
{
if(pitem!=NULL)
*pitem = p->data;
ps->size--;
ps->top = ps->top->down;
free(p);
}
return ps->top;
}

/*销毁一个栈*/
void DestroyStack(Stack *ps)
{
if(IsEmpty(ps)!=1)
ClearStack(ps);
free(ps);
}

/*把栈置空*/
void ClearStack(Stack *ps)
{
while(IsEmpty(ps)!=1)
{
Pop(ps,NULL);
}
}

/*遍历栈并访问visit函数 */
void StackTraverse(Stack *ps,void (*visit)())
{
PNode p = ps->top;
int i = ps->size;
while(i--)
{
visit(p->data);
p = p->down;
}
}

#include"Stack.h"
#include<stdio.h>
void print(Item i)
{
printf("该节点元素为%d\n",i);
}
main()
{
Stack *ps = InitStack();
int i,item;

printf("0-9依次入栈并输出如下：\n");
for(i=0;i<10;i++)
{
Push(ps,i);
GetTop(ps,&item);
printf("%d ",item);
}

printf("\n从栈顶到栈顶遍历并对每个元素执行print函数：\n");
StackTraverse(ps,print);

printf("栈中元素依次出栈并输出如下：\n");
for(i=0;i<10;i++)
{
Pop(ps,&item);
printf("%d ",item);
}

ClearStack(ps);
if(IsEmpty(ps))
printf("\n将栈置空成功\n");
DestroyStack(ps);
printf("栈已被销毁\n");

}