1 #include<stdio.h>
2 #include<stdlib.h>
3 typedef struct stack
4 {
5 char date;
6 struct stack *next;
7 }stacknode;
8
9 typedef struct
10 {
11 stacknode *top;
12 }linkstack;/*栈顶指针*/
13
14 void init_stack(linkstack *s)/*初始化栈操作*/
15 {
16 s->top=NULL;
17 }
18
19 int empty_stack(linkstack *s)
20 {
21 return(s->top==NULL);
22 }
23
24 void push_stack(linkstack *s,char ch)
25 {
26 stacknode *p;/*新建结点*/
27 p=(stacknode *)malloc(sizeof(stacknode));
28 p->next=s->top;/*如果是第一个结点，那么p->next为NULL*/
29 p->date=ch;
30 s->top=p;
31 }
32 char pop_stack(linkstack *s)
33 {
34 stacknode *p;
35 p=s->top;
36 s->top=p->next;
37 return p->date;
38
39 }
40
41 int main()
42 {
43 linkstack s;
44 char ch;
45 init_stack(&s);
46 while((ch=getchar())!='\n')
47 {
48 push_stack(&s,ch);
49 }
50 while(!empty_stack(&s))
51 {
52 printf("%c",pop_stack(&s));
53
54 }
55 }
