链栈的实现

stack.h

 1 #ifndef _STACK_H
 2 #define _STACK_H
 3 
 4 #include<stdio.h>
 5 #include<stdlib.h>
 6 
 7 typedef struct StackNode
 8 {
 9     int data;
10     struct StackNode* next;
11 }StackNode,*LinkStack;
12 
13 //初始化
14 void init(LinkStack top);
15 //判断栈是否为空
16 int isEmpty(LinkStack top);
17 //将一个元素压入栈
18 int push(LinkStack top, int val);
19 //从栈中弹出一个元素
20 int pop(LinkStack top, int *val);
21 //获取栈顶元素的值
22 int getTop(LinkStack top);
23 
24 
25 #endif

stack.c

 1 #include "stack.h"
 2 
 3 void init(LinkStack top)
 4 {
 5     top->next = NULL;
 6 }
 7 
 8 int isEmpty(LinkStack top)
 9 {
10     if(top->next == NULL)
11         return 1;
12     return 0;
13 }
14 //top指向的结点为空的头结点
15 int push(LinkStack top, int val)
16 {
17     StackNode *newNode;
18     newNode = (StackNode*)calloc(1,sizeof(StackNode));
19     newNode->data = val;
20 
21     if(newNode == NULL)
22         return 0;
23     newNode->next = top->next;
24     top->next = newNode;
25     return 1;
26 }
27 
28 
29 int pop(LinkStack top, int *val)
30 {
31     StackNode *oldNode;
32     if(isEmpty(top))
33     {
34         printf("The stack is empty!
");
35         return 0;
36     }
37     oldNode = top->next;
38     //记录栈顶元素的值
39     *val = oldNode->data;
40     top->next = oldNode->next;
41     //释放
42     free(oldNode);
43     return 1;
44 }
45 
46 int getTop(LinkStack top)
47 {
48     return top->next->data;
49 }

main.c

 1 #include "stack.h"
 2 
 3 int main()
 4 {
 5     LinkStack top;
 6     top = (StackNode*)malloc(sizeof(StackNode));
 7     int val, index;
 8     init(top);
 9 
10     //向栈中压入一系列元素
11     for(index = 0; index < 12; index++)
12         push(top,index);
13 
14     //获取栈顶元素
15     val = getTop(top);
16     printf("栈顶元素为：%d
",val);
17 
18 
19     //弹出栈中元素
20     printf("依次弹出栈顶元素:
");
21     while(!(isEmpty(top)))
22     {
23         pop(top,&val);
24         printf("->%2d",val);
25     }
26     printf("
");
27     return 0;
28 }

运行结果：