链栈-书上习题

 1 #include <iostream>
 2 #include <cstdio>
 3 using namespace std;
 4 struct stack
 5 {        
 6     char data;
 7     stack *next;
 8 };
 9 stack* initstack()            /*为栈头指针申请内存*/
10 {
11     stack *s=new stack;
12     s->next=NULL;
13     return s;
14 }
15 int isempty(stack *s)
16 {
17     if(s->next==NULL)
18         return 1;
19     return 0;
20 }
21 void pushstack(stack* s,char c)
22 {
23     stack *p=new stack;
24     p->next=s->next;
25     s->next=p;
26     p->data=c;
27 }
28 int popstack(stack *s,char *e)
29 {
30     if(isempty(s))
31         return 0;
32     else
33     {
34         stack *p=s->next;
35         s->next=p->next;
36         *e=p->data;
37         delete p;
38         return 1;
39     }
40 }
41 int main()
42 {
43     stack *s=initstack();
44     char c,e;
45     while(scanf("%c",&c)&&c!=‘\n‘)
46         pushstack(s,c);
47     while(!isempty(s))
48     {
49         popstack(s,&e);
50         cout<<e;
51     }
52 }

 1 #include <iostream>
 2 #include <cstdio>
 3 using namespace std;
 4 struct stack
 5 {
 6     char s[100];
 7     int top,bottom;
 8 };
 9 void initstack(stack* st)
10 {
11     st->top=0;
12     st->bottom=0;
13 }
14 int isempty(stack *st)
15 {
16     if(st->top==st->bottom)
17         return 1;
18     return 0;
19 }
20 void pushstack(stack* st,char c)
21 {
22     st->top++;
23     st->s[st->top]=c;
24 }
25 int popstack(stack* st,char *e)
26 {
27     if(isempty(st))
28         return 0;
29     *e=st->s[st->top];
30     st->top--;
31     return 1;
32 }
33 int main()
34 {
35     stack q;
36     initstack(&q);
37     char c,e;
38     while(scanf("%c",&c)&&c!=‘\n‘)
39         pushstack(&q,c);
40     while(!isempty(&q))
41     {
42         popstack(&q,&e);
43         cout<<e;
44     }
45 
46 }