双向链表Test1

一．实验目的
     巩固线性表的数据结构的存储方法和相关操作，学会针对具体应用，使用线性表的相关知识来解决具体问题。
 
二．.实验内容
  建立一个由n个学生成绩的顺序表，n的大小由自己确定，每一个学生的成绩信息由自己确定，实现数据的对表进行插入、删除、查找等操作。分别输出结果。
（用双向链表来实现）。

 

三．.源代码

//DoubleList.h文件

#include<iostream> using namespace std; template<class T> struct Node { T data; Node<T> *pNext; Node<T> *pPrior; }; template<class T> class List { private: Node<T> *pHead; Node<T> *pTail; int length; public: List(int length); void traverseList(); void traverseListReturn(); void sortList(); bool insert(int index, T x); bool ChangeList(int postion, int num); //修改链表中指定位置的节点 void ClearList(); int DeleteList(int postion); int GetList(int postion); ~List(); }; template<class T> List<T>::List(int length) { this->length = length; pHead = new Node<T>; pHead->pPrior = NULL; pTail = pHead; for (int i = 0; i < length; i++) { Node<T> *temp = new Node<T>; cout << "Please enter the no." << i + 1 << "Node's data:"; cin >> temp->data; temp->pNext = NULL; temp->pPrior = pTail; pTail->pNext = temp; pTail = temp; } } template<class T> void List<T>::traverseList() { Node<T> *p = pHead->pNext; while (p != NULL) { cout << p->data << " "; p = p->pNext; } cout << endl; } template<class T> void List<T>::traverseListReturn() { Node<T>*p = pTail; while (p->pPrior != NULL) { cout << p->data << " "; p = p->pPrior; } cout << endl; } template<class T> void List<T>::sortList() { Node<T> *p = new Node<T>; Node<T> *q = new Node<T>; T temp; for (p = pHead->pNext; p->pNext != NULL; p = p->pNext) { for (q = p->pNext; q != NULL; q = q->pNext) { if (q->data < p->data) { temp = q->data; q->data = p->data; p->data = temp; } } } } template<class T> bool List<T>::insert(int index, T x) { if (index<1 || index>length) { return false; } Node<T> *p = new Node<T>; p->data = x; Node<T> *q = pHead; for (int i = 0; i < index; i++) { q = q->pNext; } p->pPrior = q->pPrior; q->pPrior->pNext = p; p->pNext = q; q->pPrior = p; length++; return true; } template<class T> bool List<T>::ChangeList(int postion, int num) { Node<T> *p = pHead->pNext; if (postion > length || postion < 1) { return false; } for (int i = 0; i < postion - 1; i++) { p = p->pNext; } p->data = num; } template<class T> void List<T>::ClearList() { Node<T> *q; Node<T> *p = pHead->pNext; while (p != NULL) { q = p; p = p->pNext; delete q; } p = NULL; q = NULL; } template<class T> int List<T>::DeleteList(int postion) { Node<T> *p = pHead->pNext; if (postion > length || postion < 1) { return -1; } for (int i = 0; i < postion - 1; i++) { p = p->pNext; } p->pPrior->pNext = p->pNext; p->pNext->pPrior = p->pPrior; delete p; length--; } template<class T> int List<T>::GetList(int postion) { Node<T> *p = pHead->pNext; if (postion > length || postion < 1) { return -1; } for (int i = 0; i < postion - 1; i++) { p = p->pNext; } return p->data; } template<class T> List<T>::~List() { Node<T> *q; Node<T> *p = pHead->pNext; while (p != NULL) { q = p; p = p->pNext; delete q; } p = NULL; q = NULL; }

//源.cpp

#include"DoubleList.h"
#include<iostream>
using namespace std;
int main(void)
{
	List<float> Score(4);
	Score.traverseList(); //输入99.5.98.94.5.88，遍历
	Score.traverseListReturn(); //逆向遍历
	cout << "---------------------------" << endl;
	Score.sortList(); //排序
	Score.traverseList(); //再次遍历
	cout << "---------------------------" << endl;
	Score.insert(3, 96); //在第三个位置插入96
	Score.traverseList(); //再次遍历
	cout << "---------------------------" << endl;
	Score.ChangeList(2, 100); //将第二个位置改为100
	Score.traverseList(); //再次遍历
	cout << "---------------------------" << endl;
	Score.sortList(); //排序
	Score.traverseList(); //再次遍历
	cout << "---------------------------" << endl;
	cout << Score.GetList(2) << endl; //获取第二个位置的元素
	Score.DeleteList(3); //删除第三个位置的元素
	Score.traverseList();//再次遍历
	cout << "---------------------------" << endl;
	system("pause");
	return 0;
}

实验结果如下：

经验证，结果无误

四、实验心得

双向链表的一个特点就是有着prior和next两个指针；在双链表中，求表长、按位查找、按值查找、遍历等操作的实现与单链表基本相同。所以没什么大问题，在插入和删除操作操作时应该注意，把节点的前驱指针和后继指针都连接上，并且要注意指针修改的先后顺序，我就应该修改顺序颠倒而出现错误。

通过这次实验，掌握了双向链表的使用，也更加巩固了对线性表的深入了解。