双向链表的创建插入删除

 1 #include <iostream>
 2 #include<fstream>
 3 
 4 using namespace std;
 5 //typedef struct Node{
 6 //    int value;
 7 //    struct Node *next;
 8 //}Node;
 9 class Node{
10 public :
11     Node():data(0),last(nullptr),next(nullptr){}
12     Node(int bv,class Node* bp1,class Node* bp2):data(bv),last(bp1),next(bp2){}
13 public :
14     int data;
15     class Node* next;
16     class Node* last;
17 };
18 Node *headNode,*tailNode;
19 int listlen;
20 void initlist();
21 void inselist(int kdata);
22 void delelist();
23 void outlist();
24 
25 int main()
26 {
27     int insedata = 0;
28     cin >> listlen;
29     initlist();
30     cin >> insedata;
31     inselist(insedata);
32     outlist();
33     delelist();
34     return 0;
35 }
36 void initlist()
37 {
38     int data;
39     Node *tempNode = nullptr;
40     cin >> data;
41     headNode = new Node(data,nullptr,nullptr);
42     tempNode = headNode;
43     for(int i=1; i<listlen; ++i){
44         cin >> data;
45         tempNode->next = new Node(data,tempNode,nullptr);
46         tempNode = tempNode->next;
47     }
48     tailNode = tempNode;
49 }
50 void inselist(int kdata)
51 {
52     Node *tempNode = headNode;
53     Node *inseNode = new Node(kdata,nullptr,nullptr);
54     while(tempNode){
55         if(tempNode->data >= kdata){
56             break;
57         }
58         tempNode = tempNode->next;
59     }
60     if(tempNode == headNode){
61         headNode->last = inseNode;
62         inseNode->next = headNode;
63         headNode = inseNode;
64     }
65     else if(tempNode == nullptr){
66         tailNode->next = inseNode;
67         inseNode->last = tailNode;
68         tailNode = inseNode;
69     }
70     else{
71         (tempNode->last)->next = inseNode;
72         inseNode->last = tempNode->last;
73         inseNode->next = tempNode;
74         tempNode->last = inseNode;
75     }
76 }
77 void outlist()
78 {
79     Node *tNode = headNode;
80     ofstream outf("out.txt",ios::out);
81 
82     while(tNode){
83         if(tNode == headNode)cout << tNode->data;
84         else cout << " " << tNode->data;
85         tNode = tNode->next;
86     }
87     outf << endl;
88     outf.close();
89 }
90 void delelist()
91 {
92     Node *tNode = headNode;
93     Node *tnext;
94     while(tNode){
95         tnext = tNode->next;
96         delete tNode;
97         tNode = tnext;
98     }
99 }