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来源：互联网发布：小米的域名花了多少钱编辑：程序博客网时间：2024/05/22 08:24

栈的简单模拟题，注意一定要读清楚题意，要不然你会后悔的！自己写的代码

#include<iostream>
#include<cstdlib>
#include<cstring>
using namespace std;

#define N 80
#define M 105
typedef char elem[N];
typedef struct Stack
{
elem *base;
elem *top;
}staks;

staks forward;
staks backward;
void init(staks &s)
{
s.base=(elem *)malloc(M*sizeof(elem));
if(!s.base)
return ;
s.top=s.base;
}
void push(staks &s,elem e)
{

strcpy(*s.top,e);
s.top++;
}

int pop(staks &s,elem &e)
{
if(s.base==s.top)
  return 0;
s.top--;
strcpy(e,*s.top);
return 1;
}
int empty(staks s)
{
if(s.base==s.top)
  return 1;
else
  return 0;
}

int main()
{
char con[10],web[80];
char current[80]="http://www.acm.org/";
    init(forward);
init(backward);
while(1)
{
  scanf("%s",con);
  if(strcmp(con,"QUIT")==0)
   break;
  if(strcmp(con,"VISIT")==0)
  {
   push(backward,current);
   scanf("%s",web);
   printf("%s/n",web);
   strcpy(current,web);
   forward.top=forward.base;
  }
  else if(strcmp(con,"BACK")==0)
  {

   if(empty(backward))
     printf("Ignored/n");
   else
   {
    push(forward,current);
    pop(backward,web);
    strcpy(current,web);
    printf("%s/n",web);
   }

  }
  else if(strcmp(con,"FORWARD")==0)
  {

   if(empty(forward))
    printf("Ignored/n");
   else
   {
    push(backward,current);
    pop(forward,web);
    strcpy(current,web);
    printf("%s/n",web);

}
}
}
return 0;
}