144.链表库以及迭代算法原理

  • Node.h 
     1 #pragma once
 2 
 3 template<class T>
 4 class Node
 5 {
 6 public:
 7     T t;
 8     Node *pNext;
 9 
10 };
  • forwart_list.h 
     1 #pragma once
 2 #include "Node.h"
 3 #include <iostream>
 4 #include "it.h"
 5 using namespace std;
 6 
 7 template<class T>
 8 class forwart_list
 9 {
10 private:
11     //头结点
12     Node<T> *phead;
13 public:
14     forwart_list();
15     ~forwart_list();
16     void push_front(T &t);
17     void push_front(T &&t);
18     void push_back(T &t);
19     void push_back(T &&t);
20     void show();
21     void merge(forwart_list<T>&mylist);
22     void insert(T t, T newt);
23     Node<T>*find(T t);
24     void clear();
25     void sort();
26     void deleteit(T t);
27     int getsize();
28     void change(T t,T newt);
29     //链表反转
30     void rev();
31     it<T> begin();
32     it<T> end();
33 };
  • forward_list.cpp 
      1 #include "forwart_list.h"
  2 
  3 
  4 
  5 template<class T>
  6 forwart_list<T>::forwart_list():phead(nullptr)
  7 {
  8     
  9 }
 10 
 11 
 12 template<class T>
 13 forwart_list<T>::~forwart_list()
 14 {
 15     
 16 }
 17 
 18 template<class T>
 19 void forwart_list<T>::push_front(T & t)
 20 {
 21     //开辟节点
 22     Node<T> *pnew = new Node<T>;
 23     //赋值
 24     pnew->t = t;
 25     pnew->pNext = nullptr;
 26     if (phead == nullptr)
 27     {
 28         this->phead = pnew;
 29     }
 30     else
 31     {
 32         pnew->pNext = phead;
 33         this->phead = pnew;
 34     }
 35 }
 36 
 37 template<class T>
 38 void forwart_list<T>::push_front(T && t)
 39 {
 40     //开辟节点
 41     Node<T> *pnew = new Node<T>;
 42     //赋值
 43     pnew->t = t;
 44     pnew->pNext = nullptr;
 45     if (phead == nullptr)
 46     {
 47         this->phead = pnew;
 48     }
 49     else
 50     {
 51         pnew->pNext = phead;
 52         this->phead = pnew;
 53     }
 54 }
 55 
 56 template<class T>
 57 void forwart_list<T>::push_back(T & t)
 58 {
 59     //开辟节点
 60     Node<T> *pnew = new Node<T>;
 61     //赋值
 62     pnew->t = t;
 63     pnew->pNext = nullptr;
 64     if (phead == nullptr)
 65     {
 66         this->phead = pnew;
 67     }
 68     else
 69     {
 70         Node<T>*ptemp = phead;
 71         while (ptemp->pNext != nullptr)
 72         {
 73             ptemp = ptemp->pNext;
 74         }
 75         ptemp->pNext = pnew;
 76     }
 77 }
 78 
 79 template<class T>
 80 void forwart_list<T>::push_back(T && t)
 81 {
 82     //开辟节点
 83     Node<T> *pnew = new Node<T>;
 84     //赋值
 85     pnew->t = t;
 86     pnew->pNext = nullptr;
 87     if (phead == nullptr)
 88     {
 89         this->phead = pnew;
 90     }
 91     else
 92     {
 93         Node<T>*ptemp = phead;
 94         while (ptemp->pNext != nullptr)
 95         {
 96             ptemp = ptemp->pNext;
 97         }
 98         ptemp->pNext = pnew;
 99     }
100 }
101 
102 template<class T>
103 void forwart_list<T>::show()
104 {
105     Node<T>*ptemp = phead;
106     while (ptemp != nullptr)
107     {
108         cout << ptemp->t << endl;
109         ptemp = ptemp->pNext;
110     }
111 }
112 
113 template<class T>
114 void forwart_list<T>::merge(forwart_list<T>& mylist)
115 {
116     Node<T> *ptemp = phead;
117     while (ptemp->pNext != nullptr)
118     {
119         ptemp = ptemp->pNext;
120     }
121     //归并
122     ptemp->pNext = mylist.phead;
123 }
124 
125 template<class T>
126 void forwart_list<T>::insert(T t, T newt)
127 {
128     Node<T> *p = find(t);
129 
130     if (p != nullptr)
131     {
132         //p1记录前一个遍历的位置,p2一直遍历
133         Node<T>*p1, *p2;
134         p1 = phead;
135         p2 = phead;
136         while (p2 != p)
137         {
138             p1 = p2;
139             p2 = p2->pNext;
140         }
141 
142         Node<T>* pnew = new Node<T>;
143         pnew->t = newt;
144         pnew->pNext = p2;
145         p1->pNext = pnew;
146     }
147 }
148 
149 template<class T>
150 Node<T>* forwart_list<T>::find(T t)
151 {
152     Node<T> *ptemp = phead;
153     while (ptemp != nullptr)
154     {
155         if (ptemp->t == t)
156         {
157             return ptemp;
158         }
159         ptemp = ptemp->pNext;
160     }
161     return nullptr;
162 }
163 
164 //清空
165 template<class T>
166 void forwart_list<T>::clear()
167 {
168     if (phead == nullptr)
169     {
170         return;
171     }
172     else
173     {
174         //p2保存后一个结点,一直删除p1
175         Node<T>*p1, *p2;
176         p1 = phead;
177         while (p1 != nullptr)
178         {
179             p2 = p1->pNext;
180             delete p1;
181             p1 = nullptr;
182             p1 = p2;
183         }
184     }
185 }
186 
187 template<class T>
188 void forwart_list<T>::sort()
189 {
190     for (Node<T>*p1 = head; p1 != nullptr; p1 = p1->pNext)
191     {
192         for (Node<T>*p2 = head; p2->pNext->pNext != nullptr; p2 = p2->pNext)
193         {
194             if (p2->t > p2->pNext->t)
195             {
196                 T temp;
197                 temp = p1->t;
198                 p1->t = p2->t;
199                 p2->t = temp;
200             }
201         }
202     }
203 }
204 
205 template<class T>
206 void forwart_list<T>::deleteit(T t)
207 {
208     Node<T> *p = find(t);
209 
210     if (p != nullptr)
211     {
212         //p1记录前一个遍历的位置,p2一直遍历
213         Node<T>*p1, *p2;
214         p1 = phead;
215         p2 = phead;
216         while (p2 != p)
217         {
218             p1 = p2;
219             p2 = p2->pNext;
220         }
221 
222         if (p2 == phead)
223         {
224             phead = p->pNext;
225             delete p;
226         }
227         else
228         {
229             p1->pNext = p2->pNext;
230             delete p2;
231         }
232         p2 = nullptr;
233     }
234 }
235 
236 template<class T>
237 int forwart_list<T>::getsize()
238 {
239     int count = 0;
240     Node<T>*p;
241     while (p != nullptr)
242     {
243         p = p->pNext;
244         count++;
245     }
246     return count;
247 }
248 
249 template<class T>
250 void forwart_list<T>::change(T t, T newt)
251 {
252     Node<T> *p = find(t);
253     if (p != nullptr)
254     {
255         p -> t = newt;
256     }
257 }
258 
259 template<class T>
260 void forwart_list<T>::rev()
261 {
262     if (phead == nullptr || phead->pNext == nullptr)
263     {
264         return;
265     }
266     else
267     {
268         //p1,p2,p3分别是相对第一个位置,相对第二个位置,相对第三个位置
269         Node<T>*p1, *p2, *p3;
270         p1 = phead;
271         p2 = phead->pNext;
272         while (p2 != nullptr)
273         {
274             p3 = p2->pNext;
275             p2->pNext = p1;
276 
277             p1 = p2;
278             p2 = p3;
279         }
280         phead->pNext = nullptr;
281         phead = p1;
282     }
283 }
284 
285 template<class T>
286 it<T> forwart_list<T>::begin()
287 {
288     return it<T>(this->phead);
289 }
290 
291 template<class T>
292 it<T> forwart_list<T>::end()
293 {
294     Node<T>*ptemp = phead;
295     while (ptemp != nullptr)
296     {
297         ptemp = ptemp->pNext;
298     }
299     return it<T>(ptemp);
300 }
  • 迭代it.h 
     1 #pragma once
 2 #include "Node.h"
 3 #include <iostream>
 4 using namespace std;
 5 
 6 //通过,bgein(),end()实现迭代器,重载++
 7 template<class T>
 8 class it
 9 {
10 public:
11     Node<T>*p;
12 
13 public:
14     it():p(nullptr)
15     {
16 
17     }
18 
19     it(Node<T>* pnew) :p(pnew)
20     {
21 
22     }
23 
24     ~it()
25     {
26         if (p != nullptr)
27         {
28             //不能删除
29             //delete p;
30         }
31     }
32 
33     void operator++()
34     {
35         if (p != nullptr)
36         {
37             p = p->pNext;
38         }
39     }
40 
41     void operator++(int)
42     {
43         if (p != nullptr)
44         {
45             p = p->pNext;
46         }
47     }
48 
49     T operator *()
50     {
51         return p->t;
52     }
53 
54     Node<T>* operator ->()
55     {
56         return p;
57     }
58 
59     void showdata()
60     {
61         cout << this->p->t << endl;
62     }
63 
64     template<class T>
65     friend ostream& operator<<(ostream &out, it<T> &itt)
66     { 
67         out << itt.p->t;
68         return out;
69     }
70 
71     bool operator != (it<T> &myit)
72     {
73         if (this->p != myit.p)
74         {
75             return true;
76         }
77         else
78         {
79             return false;
80         }
81     }
82 };
  • main.cpp 
     1 #include <iostream>
 2 #include "forwart_list.h"
 3 #include "forwart_list.cpp"
 4 #include "it.h"
 5 using namespace std;
 6 
 7 template<class T,class F>
 8 void for_every(T begin,T end,F f)
 9 {
10     for (auto ib = begin; ib != end;ib++ )
11     {    
12         f(*ib);
13     }
14 }
15 
16 void main()
17 {
18     forwart_list<int> mylist;
19     for (int i = 0; i < 10; i++)
20     {
21         mylist.push_back(i);
22     }
23     //mylist.show();
24 
25     //for (auto i : mylist)
26     //{
27     //    //cout << i << endl;
28     //}
29 
30     /*for (auto i = mylist.begin(); i != mylist.end(); i++)
31     {
32         cout << i << endl;
33     }*/
34 
35     /*for (auto i : mylist)
36     {
37         cout << i << endl;
38     }*/
39     //反转
40     //mylist.rev();
41     mylist.insert(3, 5);
42     mylist.deleteit(3);
43     mylist.deleteit(5);
44     /*mylist.insert(7, 5);
45     mylist.deleteit(2);*/
46     for_every(mylist.begin(), mylist.end(), [](int num) {cout << num << endl; });
47     cin.get();
48 }
【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/xiaochi/p/8712905.html