stack.cpp

数据结构与程序设计教材源码 数据结构与程序设计教材源码

 
#include "../../4/LINKSTAC/STACK1.CPP"
 
Stack::Stack(const Stack &original) //  copy constructor
/*   
Post: The Stack is initialized as a copy of Stack original.
 */
{
   Node *new_copy, *original_node = original.top_node;
   if (original_node == NULL) top_node = NULL;
   else {                         //  Duplicate the linked nodes.
      top_node = new_copy = new Node(original_node->entry);
      while (original_node->next != NULL) {
         original_node = original_node->next;
         new_copy->next = new Node(original_node->entry);
         new_copy = new_copy->next;
      }
   }
}
 
void Stack::operator = (const Stack &original) //  Overload assignment
/*   
Post: The Stack is reset as a copy of Stack original.
 */
{
   Node *new_top, *new_copy, *original_node = original.top_node;
   if (original_node == NULL) new_top = NULL;
   else {                         //  Duplicate the linked nodes
      new_copy = new_top = new Node(original_node->entry);
      while (original_node->next != NULL) {
         original_node = original_node->next;
         new_copy->next = new Node(original_node->entry);
         new_copy = new_copy->next;
      }
   }
   while (!empty())               //  Clean out old Stack entries
      pop();
   top_node = new_top;                 //  and replace them with new entries.
}
 
Stack::~Stack() //  Destructor
/*   
Post: The Stack is cleared.
 */
{
   while (!empty())
      pop();
}