algo2-2.cpp

答案c

// algo2-2.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream>
#include <conio.h>
using namespace std;
template <class T>
struct Node
{
	T data;
	Node<T> *next;
};

template <class T>
class LinkList
{
public:
	LinkList(){head = new Node<T>; head->next = NULL;};
	LinkList(T a[],int n);
	void InitList();
	void DestroyList();
	int ListEmpty();
	int ListLength();
	void DispList();
	int GetElem(int i,T &e);
	int LocateElem(T e);
	int ListInsert(int i,T e);
	int ListDelete(int i,T &e);
private:
	Node<T> *head;
};
template <class T>
LinkList<T>::LinkList(T a[],int n)
  {      Node<T> *s;int i;
          head=new Node;  	
                      /*创建头结点*/
          head->next=NULL;
          for (i=0;i<n;i++)
          {     s=new Node<T>;
                      /*创建新结点*/
                  s->data=a[i]; s->next=head->next;		
                      /*将*s插在原开始结点之前,头结点之后*/
                  head->next=s;
           }
  }
template <class T>
void LinkList<T>::InitList()
      {
	head=new Node<T>;  	
               /*创建头结点*/
	head->next=NULL;
      }
template <class T>
void LinkList<T>::DestroyList()
    {	Node<T> *p=head,*q=p->next;
	while (q!=NULL)
	{      delete(p);
	        p=q;q=p->next;
	}
	delete(p);
    }
template <class T>
int LinkList<T>::ListEmpty()
      {
	return(head->next==NULL);
      }
template <class T>
int LinkList<T>::ListLength()
    {	Node<T> *p=head;int i=0;
	while (p->next!=NULL)
	{     i++;
	       p=p->next;
	}
	return(i);
     } 
template <class T>
void LinkList<T>::DispList()
    {	Node<T> *p=head->next;
	while (p!=NULL)
	{      cout<<p->data<<' ';
	        p=p->next;
	}
	cout<<endl;
    }
template <class T>
int LinkList<T>::GetElem(int i,T &e)
    {	int j=0;
	Node<T> *p=head;
	while (j<i && p!=NULL)
	{     j++;
	      p=p->next;
	}
	if (p==NULL) return 0; /*不存在第i个数据结点*/
	else	  /*存在第i个数据结点*/
	{    e=p->data;
	      return 1;
	}
    }
template <class T>
int LinkList<T>::LocateElem(T e)
   {	Node<T> *p=head->next;int n=1;
	while (p!=NULL && p->data!=e)
	{      p=p->next;  n++;  }
	if (p==NULL)  return 0;
	else  return n;
   }
template <class T>
int LinkList<T>::ListInsert(int i,T e)
  {    int j=0;
        Node<T> *p=head, *s;
        while (j<i-1 && p!=NULL)     /*查找第i-1个结点*/
        {     j++;
	    p=p->next;
        }
	if (p==NULL) return 0; /*未找到位序为i-1的结点*/
	else	/*找到位序为i-1的结点*p*/
	{    s=new Node<T>;
		/*创建新结点*s*/
	      s->data=e;
	      s->next=p->next;  /*将*s插入到*p之后*/
	      p->next=s;
	      return 1;
	}
}
template <class T>
int LinkList<T>::ListDelete(int i,T &e)
      {	int j=0;
	Node<T> *p=head,*q;
	while (j<i-1 && p!=NULL)  /*查找第i-1个结点*/
	{     j++;
	      p=p->next;
	}
	if (p==NULL) return 0; /*未找到位序为i-1的结点*/
	else	/*找到位序为i-1的结点*p*/
	{      q=p->next;	            /*q指向要删除的结点*/
	        if (q==NULL)   return 0;
   	                /*若不存在第i个结点,返回0*/
	        p->next=q->next;	 /*从单链表中删除*q结点*/
	        delete(q);	                         /*释放*q结点*/
	        return 1;
	}
    }
int main()
{
	char X, Y;
	LinkList<char> h;
	cout<<"InitList"<<endl;	
	h.InitList();
	
	cout<<"Insert a,b,c,d,e"<<endl;
	h.ListInsert(1, 'a');
	h.ListInsert(2, 'b');
	h.ListInsert(3, 'c');
	h.ListInsert(4, 'd');
	h.ListInsert(5, 'e');

	cout<<"DisplayList"<<endl;
	h.DispList();

	cout<<"ListLength is "<<h.ListLength()<<endl;

	if(h.ListEmpty())cout<<"List Is Empty"<<endl;
	else cout<<"List Isn't Empty"<<endl;
	h.GetElem(2 ,X);
	cout<<"Elem 2 Is "<<X<<endl;

	cout<<"Elem 'a' is at place "<<h.LocateElem('a');

	cout<<"Insert f"<<endl;
	h.ListInsert(4, 'f');

	cout<<"DisplayList"<<endl;
	h.DispList();

	cout<<"Delete Elem at place 3 is ";
	h.ListDelete(3, Y);
	cout<<X<<endl;

	cout<<"DisplayList"<<endl;
	h.DispList();

	cout<<"DestroyList"<<endl;
	h.DestroyList();

	_getch();

	return 0;
}