C++语言实现双向链表（广州大学某次作业）

桃扇骨 2022-05-26 04:42 29阅读 0赞

要求是:设计双向链表存储矩形的长跟宽，然后存下来面积，最后根据面积排序，要实现文件的IO

#include<iostream>
    #include <fstream>
    using namespace std;
    class Node          //组成双向链表的节点
    {
     public:
         int lgth;  //长度
         int width;  //宽度
         int area;   //面积
         Node * pNext;
         Node * pLast;
    };
    
    class List
    {
    private:
        Node * pHead;
        Node * pTail;
        int length;
    public:
        List(int length)
        {
            this->length=length;
            pHead=new Node();
            pHead->pLast=NULL;
            pTail=pHead;
            for(int i=0;i<length;i++)
            {
                Node * temp=new Node();
                cout<<"please enter the no"<<i+1<<" Node's data:";
                cin>>temp->lgth>>temp->width;
                temp->area = temp->lgth*temp->width;
                temp->pNext=NULL;
                temp->pLast=pTail;
                pTail->pNext=temp;
                pTail=temp;
            }
        }
    
        void traverseList()        //正向遍历
        {
            Node * p=pHead->pNext;
            while(p!=NULL)
            {
                cout<<p->area<<endl;
                p=p->pNext;
            }
        }
    
         void WriteListIntoFile()        //写进文件
        {
            ofstream fout( "f:\\mytest.txt" );
            if ( ! fout)
            {
                cout << "文件不能打开" <<endl;
            }
            else
            {
                Node * p=pHead->pNext;
                while(p!=NULL)
                {
                    fout<<p->lgth<<" "<<p->width<<" "<<p->area<<endl;
                    p=p->pNext;
                }
            }
        }
    
        void traverseListReturn()  //逆向遍历
        {
            Node * p=pTail;
            while(p->pLast!=NULL)
            {
                cout<<p->area<<endl;
                p=p->pLast;
            }
        }
    
        void sortList()     //冒泡排序，只是交换了某个信息，没有交换所有的信息
        {
            Node * p=new Node();
            Node * q=new Node();
            int temp;
            for(p=pHead->pNext;p->pNext!=NULL;p=p->pNext)
            {
                for(q=p->pNext;q!=NULL;q=q->pNext)
                {
                    if(q->area<p->area)
                    {
                        temp=q->area;
                        q->area=p->area;
                        p->area=temp;
                    }
                }
            }
        }
    
        void sortListByInsertWay()        //插入排序
        {
            if(pHead->pNext==NULL||pHead->pNext->pNext==NULL)
            {
                return;
            }
            Node * p2=pHead->pNext->pNext;
            Node * p1=pHead;
            pHead->pNext->pNext=NULL;
            while(p2)
            {
                Node * pN=p2->pNext;
                while(p1->pNext)
                {
                    if(p2->area<p1->pNext->area)
                    {
                        p2->pNext=p1->pNext;
                        p2->pLast=p1;
                        p1->pNext->pLast=p2;
                        p1->pNext=p2;
                        break;
                    }
                    p1=p1->pNext;
                }
                if(p1->pNext==NULL)
                {
                    p2->pNext=NULL;
                    p2->pLast=p1;
                    p1->pNext=p2;
                }
                p2=pN;
            }
    
            //重新查找pTail的位置
            Node * pt=pHead;
            while(pt->pNext)
            {
                pt=pt->pNext;
            }
            pTail=pt;
        }
    
        void changeList(int num,int position) //修改链表中指定位置的节点,修改面积信息
        {
            Node * p=pHead->pNext;
            if(position>length||position<=0)
            {
                cout<<"over stack !"<<endl;
                return;
            }
            for(int i=0;i<position-1;i++)
            {
                p=p->pNext;
            }
            p->area=num;
        }
    
        void insertList(int lgth,int width,int position) //插入数据
        {
            Node * p=pHead->pNext;
            if(position>length||position<=0)
            {
                cout<<"over stack !"<<endl;
                return;
            }
            for(int i=0;i<position-1;i++)
            {
                p=p->pNext;
            }
            Node * temp=new Node();
            temp->lgth=lgth;
            temp->width = width;
            temp->area = temp->lgth*temp->width;
            temp->pNext=p;
            temp->pLast=p->pLast;
            p->pLast->pNext=temp;
            p->pLast=temp;
            length++;
        }
    
        void clearList() //清空
        {
            Node * q;
            Node * p=pHead->pNext;
            while(p!=NULL)
            {
                q=p;
                p=p->pNext;
                delete q;
            }
            p=NULL;
            q=NULL;
        }
    
        void deleteList(int position) //删除指定位置的节点
        {
            Node * p=pHead->pNext;
            if(position>length||position<=0)
            {
                cout<<"over stack !"<<endl;
                return;
            }
            for(int i=0;i<position-1;i++)
            {
                p=p->pNext;
            }
            p->pLast->pNext=p->pNext;
            p->pNext->pLast=p->pLast;
            delete p;
            length--;
        }
    
        int getItemInList(int position)  //查找指定位置的节点 ,返回面积信息
        {
            Node * p=pHead->pNext;
            if(position>length||position<=0)
            {
                cout<<"over stack !"<<endl;
                return 0;
            }
            for(int i=0;i<position-1;i++)
            {
                p=p->pNext;
            }
            return p->area;
        }
    
        ~List()
        {
            Node * q;
            Node * p=pHead->pNext;
            while(p!=NULL)
            {
                q=p;
                p=p->pNext;
                delete q;
            }
            p=NULL;
            q=NULL;
        }
    
    };
    
    int main()
    {
        int num = 0;
        printf("write in your list nums:");
        scanf("%d",&num);
        List l(num);
        l.traverseList();
        cout<<"AFTER SORT-------------------------------------------------------"<<endl;
        l.sortList();             //冒泡排序
        //l.sortListByInsertWay(); //插入排序
        l.traverseList();
        cout<<"AFTER INSERT-----------------------------------------------------"<<endl;
        l.insertList(55,20,1);
        l.traverseList();
        cout<<"AFTER DELETE-----------------------------------------------------"<<endl;
        l.deleteList(1);
        l.traverseList();
        cout<<"Return Traverse--------------------------------------------------"<<endl;
        l.traverseListReturn();
        cout<<"Write FILE-------------------------------------------------------"<<endl;
        l.WriteListIntoFile();
        cout<<"Find the Second Node's data:"<<l.getItemInList(2)<<endl;
        return 0;
    }