C ++; two-way cyclic linked list

C ++; two-way cyclic linked list

# Pragma once // header file using namespace std; typedef int DataType; class ListNode {friend class DoubleList; private: ype _ data; ListNode * _ next; ListNode * _ prev; public: listNode () ;}; class DoubleList {private: ListNode * _ pHead; ListNode * _ pTail; public: DoubleList (); DoubleList (const DoubleList & list );~ DoubleList (); void PushBack (const DataType x); void PopBack (); void Insert (ListNode * pos, const DataType x); void Erase (ListNode * pos ); listNode * Find (const DataType x); void Reverse (); void GetData (); void Destroy (); void operator = (const DoubleList & list );}; # include <iostream> // function file # include "doubleList. h "# include <assert. h> using namespace std; ListNode: ListNode (): _ next (NULL), _ prev (NULL) {} Doubl EList: DoubleList (): _ pHead (new ListNode), _ pTail (_ pHead) {_ pHead-> _ next = _ pHead; _ pHead-> _ prev = _ pHead;} DoubleList: DoubleList (const DoubleList & list) {_ pHead = new ListNode; ListNode * head = _ pHead; _ pTail = _ pHead; ListNode * tmp = list. _ pHead-> _ next; while (tmp! = List. _ pHead) {head-> _ next = new ListNode; head-> _ next-> _ data = tmp-> _ data; _ pTail = head-> _ next; _ pTail-> _ prev = head; _ pTail-> _ next = _ pHead; _ pHead-> _ prev = _ pTail; head = head-> _ next; tmp = tmp-> _ next;} DoubleList ::~ DoubleList () {while (_ pTail! = _ PHead) {ListNode * del = _ pTail; _ pTail = _ pTail-> _ prev; delete del;} delete _ pTail;} void DoubleList :: pushBack (const DataType x) {ListNode * tmp = new ListNode; tmp-> _ prev = _ pTail; _ pTail-> _ next = tmp; tmp-> _ data = x; _ pTail = tmp; tmp-> _ next = _ pHead; _ pHead-> _ prev = tmp;} void DoubleList: PopBack () {ListNode * del = _ pTail; if (_ pTail! = _ PHead) {_ pTail = _ pTail-> _ prev; _ pTail-> _ next = _ pHead;} delete del;} void DoubleList: Insert (ListNode * pos, const DataType x) {assert (pos); ListNode * tmp = new ListNode; tmp-> _ prev = pos; tmp-> _ next = pos-> _ next; pos-> _ next = tmp; tmp-> _ next-> _ prev = tmp; tmp-> _ data = x; _ pTail = _ pHead-> _ prev ;} void DoubleList: Erase (ListNode * pos) {assert (pos); ListNode * del = pos; if (_ pTail! = _ PHead) {pos-> _ next-> _ prev = pos-> _ prev; pos-> _ prev-> _ next = pos-> _ next ;} delete del;} ListNode * DoubleList: Find (const DataType x) {ListNode * tmp = _ pHead-> _ next; while (tmp! = _ PHead) {if (tmp-> _ data = x) {return tmp;} tmp = tmp-> _ next;} return NULL;} void DoubleList :: getData () {ListNode * tmp = _ pHead-> _ next; while (tmp! = _ PHead) {cout <tmp-> _ data <"->"; tmp = tmp-> _ next;} cout <"NULL" <endl ;} void DoubleList: Reverse () {ListNode * tmp = _ pHead-> _ next; ListNode * newHead = _ pHead; do {newHead-> _ next = newHead-> _ prev; newHead-> _ prev = tmp; newHead = tmp; tmp = newHead-> _ next;} while (newHead! = _ PHead); _ pTail = _ pHead-> _ prev;} void DoubleList: Destroy () {this-> ~ DoubleList ();} void DoubleList: operator = (const DoubleList & list) {_ pHead = new ListNode; ListNode * head = _ pHead; _ pTail = _ pHead; listNode * tmp = list. _ pHead-> _ next; while (tmp! = List. _ pHead) {head-> _ next = new ListNode; head-> _ next-> _ data = tmp-> _ data; _ pTail = head-> _ next; _ pTail-> _ prev = head; _ pTail-> _ next = _ pHead; _ pHead-> _ prev = _ pTail; head = head-> _ next; tmp = tmp-> _ next; }}# include <iostream> // main function test file # include "doubleList. h "using namespace std; void test1 () {DoubleList s1; s1.PushBack (1); s1.PushBack (2); s1.PushBack (3); s1.PushBack (4); s1.GetData (); cout <(s1.Find (1) <endl; s1.Insert (s1.Find (4), 5); s1.GetData (); DoubleList s2; s2.GetData (); s1.Reverse (); s1.GetData (); s2 = s1; s2.GetData () ;}int main () {test1 (); return 0 ;}