c语言+双向循环链表
In this tutorial you will learn about doubly linked list in C and C++.
在本教程中，您将学习C和C ++中的双向链表。
In singly linked list, we can move/traverse only in one single direction because each node has the address of the next node only. Suppose we are in the middle of the linked list and we want the address of previous node then we don’t have any option other than repeating the traversing from the beginning node.
在单链列表中 ，我们只能在一个方向上移动/遍历，因为每个节点仅具有下一个节点的地址。 假设我们在链接列表的中间，并且想要上一个节点的地址，那么除了重复从起始节点的遍历之外，没有其他选择。
To overcome this drawback, a doubly linked list can be used. In this, there are two pointers. One of these pointers points to the next node and the other points to the previous node.
为了克服这个缺点，可以使用双向链表。 在这里，有两个指针。 这些指针之一指向下一个节点，其他指针指向前一个节点。
The structure for a doubly linked list node can be declared as:
双向链表节点的结构可以声明为：
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struct node
{
struct node *prev_node;
int info;
struct node *next_node;
};
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struct node
{
struct node * prev_node ;
int info ;
struct node * next_node ;
} ;
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prev_node would contain a pointer to the address of the previous node and next_node would point the next node in the list. Hence, we can move in both the directions.
prev_node将包含指向上一个节点的地址的指针，next_node将指向列表中的下一个节点。 因此，我们可以在两个方向上移动。
遍历 (Traversing)
Traversal of a doubly linked list is similar to that of a singly linked list. We have to first check for a condition: whether the linked list is empty or not. This helps to set the start pointer at a proper location. After that we access each node till end.
双向链表的遍历与单链表的遍历相似。 我们首先要检查一个条件：链表是否为空。 这有助于将起始指针设置在正确的位置。 之后，我们访问每个节点直到结束。
插入 (Insertion)
A new node can be inserted very easily in a doubly linked list. We just need to set the pointers prev_node and next_node carefully interlinking the prev_node and the next_node node with the appropriate pointers.
一个新节点可以很容易地插入到双向链表中。 我们只需要设置指针prev_node和next_node即可仔细地将prev_node和next_node节点与适当的指针互连。
If you’re inserting a Node n2 between Node n1 and n3, you should set the pointer prev_node of n2 to n1 and pointer next_node of n2 to n3.
如果要在节点n1和n3之间插入节点n2，则应将n2的指针prev_node设置为n1，将n2的next_node指针设置为n3。
Insertion in a doubly linked list can be done in multiple ways:
插入双向链接列表可以通过多种方式完成：
1. Insertion in between the nodes. 2. Insertion at the beginning. 3. Insertion in an empty list. 4. Insertion at the end of the list.
1.插入节点之间。 2.开始插入。 3.插入一个空列表。 4.在列表末尾插入。
删除中 (Deletion)
A node can be deleted very easily in a doubly linked list. We just need to set the pointers prev_node and next_node logically to the nodes.
可以很容易地在双向链表中删除节点。 我们只需要在逻辑上将指针prev_node和next_node设置为节点即可。
Deletion of the nodes can be done in the following ways: 1. Delete at the end. 2. Delete the first node. 3. Delete in between the nodes.
可以通过以下方式 删除 节点： 1.最后删除。 2.删除第一个节点。 3.在节点之间删除。
反转双链表 (Reverse a Doubly Linked List)
Assume we have four nodes n1, n2, n3 and n4
假设我们有四个节点n1，n2，n3和n4
Steps to reverse
扭转步骤
1. Pointer begin points to the last node n4. 2. Since, the n4 is the first node now, its prev_node pointer must be NULL. 3. Node n1 is the last node, hence its next_node must be NULL. 4. Pointer next_node of n4 points to n3, next_node of n3 points to n2 and next_node of n2 points to n1. 5. Pointer prev_node of n1 points to n2, prev_node of n2 points to n3 and prev_node of n3 points to n4.
1.指针开始指向最后一个节点n4。 2.由于n4现在是第一个节点，因此其prev_node指针必须为NULL。 3.节点n1是最后一个节点，因此其next_node必须为NULL。 4. n4的指针next_node指向n3，n3的next_node指向n2，n2的next_node指向n1。 5. n1的指针prev_node指向n2，n2的prev_node指向n3，n3的prev_node指向n4。
C语言双链表程序 (Program for Doubly Linked List in C)
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#include<stdlib.h>
#include<stdio.h>
struct node
{
struct node *prev_node;
int info;
struct node *next_node;
};
struct node *create_list(struct node *begin);
void display(struct node *begin);
struct node *addtoemptylist(struct node *begin,int data_element);
struct node *addatbeglist(struct node *begin,int data_element);
struct node *addatendlist(struct node *begin,int data_element);
struct node *addafterlist(struct node *begin,int data_element,int item_pos);
struct node *addbeforelist(struct node *begin,int data_element,int item_pos);
struct node *deletenode(struct node *begin,int data_element);
struct node *reverselist(struct node *begin);
main()
{
int option,data_element,item_pos;
struct node *begin=NULL;
while(1)
{
printf("\n1.Create A New Doubly Linked List\n");
printf("2.Display the Doubly Linked List\n");
printf("3.Add to an Empty Doubly Linked List\n");
printf("4.Add at Starting of the Doubly Linked List\n");
printf("5.Add at Ending\n");
printf("6.Add After a Node\n");
printf("7.Add Before a Node\n");
printf("8.Delete a Node\n");
printf("9.Reverse the Doubly Linked List\n");
printf("10.Exit\n");
printf("Enter your option : ");
scanf("%d",&option);
switch(option)
{
case 1:
begin=create_list(begin);
break;
case 2:
display(begin);
break;
case 3:
printf("Enter the element:");
scanf("%d",&data_element);
begin=addtoemptylist(begin,data_element);
break;
case 4:
printf("Enter the element:");
scanf("%d",&data_element);
begin=addatbeglist(begin,data_element);
break;
case 5:
printf("Enter the element:");
scanf("%d",&data_element);
begin=addatendlist(begin,data_element);
break;
case 6:
printf("Enter the element:");
scanf("%d",&data_element);
printf("Enter the element after which to insert : ");
scanf("%d",&item_pos);
begin=addafterlist(begin,data_element,item_pos);
break;
case 7:
printf("Enter the element: ");
scanf("%d",&data_element);
printf("Enter the element before which to insert : ");
scanf("%d",&item_pos);
begin=addbeforelist(begin,data_element,item_pos);
break;
case 8:
printf("Enter the element to be Deleted : ");
scanf("%d",&data_element);
begin=deletenode(begin,data_element);
break;
case 9:
begin=reverselist(begin);
break;
case 10:
exit(1);
default:
printf("Wrong option\n");
}
}
}
struct node *create_list(struct node *begin)
{
int i,n,data_element;
printf("Enter the number of nodes : ");
scanf("%d",&n);
begin=NULL;
if(n==0)
return begin;
printf("Enter the element: ");
scanf("%d",&data_element);
begin=addtoemptylist(begin,data_element);
for(i=2;i<=n;i++)
{
printf("Enter the element to be inserted : ");
scanf("%d",&data_element);
begin=addatendlist(begin,data_element);
}
return begin;
}
void display(struct node *begin)
{
struct node *p;
if(begin==NULL)
{
printf("List is empty\n");
return;
}
p=begin;
printf("List is :\n");
while(p!=NULL)
{
printf("%d ",p->info);
p=p->next_node;
}
printf("\n");
}
struct node *addtoemptylist(struct node *begin,int data_element)
{
struct node *temp;
temp=(struct node *)malloc(sizeof(struct node));
temp->info=data_element;
temp->prev_node=NULL;
temp->next_node=NULL;
begin=temp;
return begin;
}
struct node *addatbeglist(struct node *begin,int data_element)
{
if(begin==NULL)
{
printf("List is empty\n");
return;
}
struct node *temp;
temp = (struct node *)malloc(sizeof(struct node));
temp->info=data_element;
temp->prev_node=NULL;
temp->next_node=begin;
begin->prev_node=temp;
begin=temp;
return begin;
}
struct node *addatendlist(struct node *begin,int data_element)
{
if(begin==NULL)
{
printf("List is empty\n");
return;
}
struct node *temp,*p;
temp=(struct node *)malloc(sizeof(struct node));
temp->info=data_element;
p=begin;
while(p->next_node!=NULL)
p=p->next_node;
p->next_node=temp;
temp->next_node=NULL;
temp->prev_node=p;
return begin;
}
struct node *addafterlist(struct node *begin,int data_element,int item_pos)
{
struct node *temp,*p;
temp=(struct node *)malloc(sizeof(struct node));
temp->info=data_element;
p=begin;
while(p!=NULL)
{
if(p->info==item_pos)
{
temp->prev_node=p;
temp->next_node=p->next_node;
if(p->next_node!=NULL)
p->next_node->prev_node=temp;
p->next_node=temp;
return begin;
}
p=p->next_node;
}
printf("%d not present in the list\n\n",item_pos);
return begin;
}
struct node *addbeforelist(struct node *begin,int data_element,int item_pos)
{
struct node *temp,*q;
if(begin==NULL )
{
printf("List is empty\n");
return begin;
}
if(begin->info==item_pos)
{
temp = (struct node *)malloc(sizeof(struct node));
temp->info=data_element;
temp->prev_node=NULL;
temp->next_node=begin;
begin->prev_node=temp;
begin=temp;
return begin;
}
q=begin;
while(q!=NULL)
{
if(q->info==item_pos)
{
temp=(struct node *)malloc(sizeof(struct node));
temp->info=data_element;
temp->prev_node=q->prev_node;
temp->next_node = q;
q->prev_node->next_node=temp;
q->prev_node=temp;
return begin;
}
q=q->next_node;
}
printf("%d not present in the list\n",item_pos);
return begin;
}
struct node *deletenode(struct node *begin,int data_element)
{
struct node *temp;
if(begin==NULL)
{
printf("List is empty\n");
return begin;
}
if(begin->next_node==NULL)
if(begin->info==data_element)
{
temp=begin;
begin=NULL;
free(temp);
return begin;
}
else
{
printf("Element %d not found\n",data_element);
return begin;
}
if(begin->info==data_element)
{
temp=begin;
begin=begin->next_node;
begin->prev_node=NULL;
free(temp);
return begin;
}
temp=begin->next_node;
while(temp->next_node!=NULL )
{
if(temp->info==data_element)
{
temp->prev_node->next_node=temp->next_node;
temp->next_node->prev_node=temp->prev_node;
free(temp);
return begin;
}
temp=temp->next_node;
}
if(temp->info==data_element)
{
temp->prev_node->next_node=NULL;
free(temp);
return begin;
}
printf("Element %d not found\n",data_element);
return begin;
}
struct node *reverselist(struct node *begin)
{
if(begin==NULL)
{
printf("List is empty\n");
return begin;
}
struct node *p1,*p2;
p1=begin;
p2=p1->next_node;
p1->next_node=NULL;
p1->prev_node=p2;
while(p2!=NULL)
{
p2->prev_node=p2->next_node;
p2->next_node=p1;
p1=p2;
p2=p2->prev_node;
}
begin=p1;
printf("List reverselistd\n");
return begin;
}
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C ++中的双链表程序 (Program for Doubly Linked List in C++)
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#include<iostream>
#include<stdlib.h>
using namespace std;
struct node
{
struct node *prev_node;
int info;
struct node *next_node;
};
struct node *create_list(struct node *begin);
void display(struct node *begin);
struct node *addtoemptylist(struct node *begin,int data_element);
struct node *addatbeglist(struct node *begin,int data_element);
struct node *addatendlist(struct node *begin,int data_element);
struct node *addafterlist(struct node *begin,int data_element,int item_pos);
struct node *addbeforelist(struct node *begin,int data_element,int item_pos);
struct node *deletenode(struct node *begin,int data_element);
struct node *reverselist(struct node *begin);
int main()
{
int option,data_element,item_pos;
struct node *begin=NULL;
while(1)
{
cout<<"\n1.Create A New Doubly Linked List\n";
cout<<"2.Display the Doubly Linked List\n";
cout<<"3.Add to an Empty Doubly Linked List\n";
cout<<"4.Add at Starting of the Doubly Linked List\n";
cout<<"5.Add at Ending\n";
cout<<"6.Add After a Node\n";
cout<<"7.Add Before a Node\n";
cout<<"8.Delete a Node\n";
cout<<"9.Reverse the Doubly Linked List\n";
cout<<"10.Exit\n";
cout<<"Enter your option : ";
cin>>option;
switch(option)
{
case 1:
begin=create_list(begin);
break;
case 2:
display(begin);
break;
case 3:
cout<<"Enter the element:";
cin>>data_element;
begin=addtoemptylist(begin,data_element);
break;
case 4:
cout<<"Enter the element:";
cin>>data_element;
begin=addatbeglist(begin,data_element);
break;
case 5:
cout<<"Enter the element:";
cin>>data_element;
begin=addatendlist(begin,data_element);
break;
case 6:
cout<<"Enter the element:";
cin>>data_element;
cout<<"Enter the element after which to insert : ";
cin>>item_pos;
begin=addafterlist(begin,data_element,item_pos);
break;
case 7:
cout<<"Enter the element: ";
cin>>data_element;
cout<<"Enter the element before which to insert : ";
cin>>item_pos;
begin=addbeforelist(begin,data_element,item_pos);
break;
case 8:
cout<<"Enter the element to be Deleted : ";
cin>>data_element;
begin=deletenode(begin,data_element);
break;
case 9:
begin=reverselist(begin);
break;
case 10:
exit(1);
default:
cout<<"Wrong option\n";
}
}
return 0;
}
struct node *create_list(struct node *begin)
{
int i,n,data_element;
cout<<"Enter the number of nodes : ";
cin>>n;
begin=NULL;
if(n==0)
return begin;
cout<<"Enter the element: ";
cin>>data_element;
begin=addtoemptylist(begin,data_element);
for(i=2;i<=n;i++)
{
cout<<"Enter the element to be inserted : ";
cin>>data_element;
begin=addatendlist(begin,data_element);
}
return begin;
}
void display(struct node *begin)
{
struct node *p;
if(begin==NULL)
{
cout<<"List is empty\n";
return;
}
p=begin;
cout<<"List is :\n";
while(p!=NULL)
{
cout<<p->info<<" ";
p=p->next_node;
}
cout<<"\n";
}
struct node *addtoemptylist(struct node *begin,int data_element)
{
struct node *temp;
temp=new struct node;
temp->info=data_element;
temp->prev_node=NULL;
temp->next_node=NULL;
begin=temp;
return begin;
}
struct node *addatbeglist(struct node *begin,int data_element)
{
if(begin==NULL)
{
cout<<"List is empty\n";
return begin;
}
struct node *temp;
temp = new struct node;
temp->info=data_element;
temp->prev_node=NULL;
temp->next_node=begin;
begin->prev_node=temp;
begin=temp;
return begin;
}
struct node *addatendlist(struct node *begin,int data_element)
{
if(begin==NULL)
{
cout<<"List is empty\n";
return begin;
}
struct node *temp,*p;
temp=new struct node;
temp->info=data_element;
p=begin;
while(p->next_node!=NULL)
p=p->next_node;
p->next_node=temp;
temp->next_node=NULL;
temp->prev_node=p;
return begin;
}
struct node *addafterlist(struct node *begin,int data_element,int item_pos)
{
struct node *temp,*p;
temp=new struct node;
temp->info=data_element;
p=begin;
while(p!=NULL)
{
if(p->info==item_pos)
{
temp->prev_node=p;
temp->next_node=p->next_node;
if(p->next_node!=NULL)
p->next_node->prev_node=temp;
p->next_node=temp;
return begin;
}
p=p->next_node;
}
cout<<item_pos<<" not present in the list\n\n";
return begin;
}
struct node *addbeforelist(struct node *begin,int data_element,int item_pos)
{
struct node *temp,*q;
if(begin==NULL )
{
cout<<"List is empty\n";
return begin;
}
if(begin->info==item_pos)
{
temp = new struct node;
temp->info=data_element;
temp->prev_node=NULL;
temp->next_node=begin;
begin->prev_node=temp;
begin=temp;
return begin;
}
q=begin;
while(q!=NULL)
{
if(q->info==item_pos)
{
temp=new struct node;
temp->info=data_element;
temp->prev_node=q->prev_node;
temp->next_node = q;
q->prev_node->next_node=temp;
q->prev_node=temp;
return begin;
}
q=q->next_node;
}
cout<<item_pos<<" not present in the list\n";
return begin;
}
struct node *deletenode(struct node *begin,int data_element)
{
struct node *temp;
if(begin==NULL)
{
cout<<"List is empty\n";
return begin;
}
if(begin->next_node==NULL)
if(begin->info==data_element)
{
temp=begin;
begin=NULL;
delete(temp);
return begin;
}
else
{
cout<<"Element "<<data_element<<" not found\n";
return begin;
}
if(begin->info==data_element)
{
temp=begin;
begin=begin->next_node;
begin->prev_node=NULL;
delete(temp);
return begin;
}
temp=begin->next_node;
while(temp->next_node!=NULL )
{
if(temp->info==data_element)
{
temp->prev_node->next_node=temp->next_node;
temp->next_node->prev_node=temp->prev_node;
delete(temp);
return begin;
}
temp=temp->next_node;
}
if(temp->info==data_element)
{
temp->prev_node->next_node=NULL;
delete(temp);
return begin;
}
cout<<"Element "<<data_element<<" not found\n";
return begin;
}
struct node *reverselist(struct node *begin)
{
if(begin==NULL)
{
cout<<"List is empty\n";
return begin;
}
struct node *p1,*p2;
p1=begin;
p2=p1->next_node;
p1->next_node=NULL;
p1->prev_node=p2;
while(p2!=NULL)
{
p2->prev_node=p2->next_node;
p2->next_node=p1;
p1=p2;
p2=p2->prev_node;
}
begin=p1;
cout<<"List reverselistd\n";
return begin;
}
|
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|
#include<iostream>
#include<stdlib.h>
using namespace std ;
struct node
{
struct node * prev_node ;
int info ;
struct node * next_node ;
} ;
struct node * create_list ( struct node * begin ) ;
void display ( struct node * begin ) ;
struct node * addtoemptylist ( struct node * begin , int data_element ) ;
struct node * addatbeglist ( struct node * begin , int data_element ) ;
struct node * addatendlist ( struct node * begin , int data_element ) ;
struct node * addafterlist ( struct node * begin , int data_element , int item_pos ) ;
struct node * addbeforelist ( struct node * begin , int data_element , int item_pos ) ;
struct node * deletenode ( struct node * begin , int data_element ) ;
struct node * reverselist ( struct node * begin ) ;
int main ( )
{
int option , data_element , item_pos ;
struct node * begin = NULL ;
while ( 1 )
{
cout << "\n1.Create A New Doubly Linked List\n" ;
cout << "2.Display the Doubly Linked List\n" ;
cout << "3.Add to an Empty Doubly Linked List\n" ;
cout << "4.Add at Starting of the Doubly Linked List\n" ;
cout << "5.Add at Ending\n" ;
cout << "6.Add After a Node\n" ;
cout << "7.Add Before a Node\n" ;
cout << "8.Delete a Node\n" ;
cout << "9.Reverse the Doubly Linked List\n" ;
cout << "10.Exit\n" ;
cout << "Enter your option : " ;
cin >> option ;
switch ( option )
{
case 1 :
begin = create_list ( begin ) ;
break ;
case 2 :
display ( begin ) ;
break ;
case 3 :
cout << "Enter the element:" ;
cin >> data_element ;
begin = addtoemptylist ( begin , data_element ) ;
break ;
case 4 :
cout << "Enter the element:" ;
cin >> data_element ;
begin = addatbeglist ( begin , data_element ) ;
break ;
case 5 :
cout << "Enter the element:" ;
cin >> data_element ;
begin = addatendlist ( begin , data_element ) ;
break ;
case 6 :
cout << "Enter the element:" ;
cin >> data_element ;
cout << "Enter the element after which to insert : " ;
cin >> item_pos ;
begin = addafterlist ( begin , data_element , item_pos ) ;
break ;
case 7 :
cout << "Enter the element: " ;
cin >> data_element ;
cout << "Enter the element before which to insert : " ;
cin >> item_pos ;
begin = addbeforelist ( begin , data_element , item_pos ) ;
break ;
case 8 :
cout << "Enter the element to be Deleted : " ;
cin >> data_element ;
begin = deletenode ( begin , data_element ) ;
break ;
case 9 :
begin = reverselist ( begin ) ;
break ;
case 10 :
exit ( 1 ) ;
default :
cout << "Wrong option\n" ;
}
}
return 0 ;
}
struct node * create_list ( struct node * begin )
{
int i , n , data_element ;
cout << "Enter the number of nodes : " ;
cin >> n ;
begin = NULL ;
if ( n == 0 )
return begin ;
cout << "Enter the element: " ;
cin >> data_element ;
begin = addtoemptylist ( begin , data_element ) ;
for ( i = 2 ; i <= n ; i ++ )
{
cout << "Enter the element to be inserted : " ;
cin >> data_element ;
begin = addatendlist ( begin , data_element ) ;
}
return begin ;
}
void display ( struct node * begin )
{
struct node * p ;
if ( begin == NULL )
{
cout << "List is empty\n" ;
return ;
}
p = begin ;
cout << "List is :\n" ;
while ( p != NULL )
{
cout << p -> info << " " ;
p = p -> next_node ;
}
cout << "\n" ;
}
struct node * addtoemptylist ( struct node * begin , int data_element )
{
struct node * temp ;
temp = new struct node ;
temp -> info = data_element ;
temp -> prev_node = NULL ;
temp -> next_node = NULL ;
begin = temp ;
return begin ;
}
struct node * addatbeglist ( struct node * begin , int data_element )
{
if ( begin == NULL )
{
cout << "List is empty\n" ;
return begin ;
}
struct node * temp ;
temp = new struct node ;
temp -> info = data_element ;
temp -> prev_node = NULL ;
temp -> next_node = begin ;
begin -> prev_node = temp ;
begin = temp ;
return begin ;
}
struct node * addatendlist ( struct node * begin , int data_element )
{
if ( begin == NULL )
{
cout << "List is empty\n" ;
return begin ;
}
struct node * temp , * p ;
temp = new struct node ;
temp -> info = data_element ;
p = begin ;
while ( p -> next_node != NULL )
p = p -> next_node ;
p -> next_node = temp ;
temp -> next_node = NULL ;
temp -> prev_node = p ;
return begin ;
}
struct node * addafterlist ( struct node * begin , int data_element , int item_pos )
{
struct node * temp , * p ;
temp = new struct node ;
temp -> info = data_element ;
p = begin ;
while ( p != NULL )
{
if ( p -> info == item_pos )
{
temp -> prev_node = p ;
temp -> next_node = p -> next_node ;
if ( p -> next_node != NULL )
p -> next_node -> prev_node = temp ;
p -> next_node = temp ;
return begin ;
}
p = p -> next_node ;
}
cout << item_pos << " not present in the list\n\n" ;
return begin ;
}
struct node * addbeforelist ( struct node * begin , int data_element , int item_pos )
{
struct node * temp , * q ;
if ( begin == NULL )
{
cout << "List is empty\n" ;
return begin ;
}
if ( begin -> info == item_pos )
{
temp = new struct node ;
temp -> info = data_element ;
temp -> prev_node = NULL ;
temp -> next_node = begin ;
begin -> prev_node = temp ;
begin = temp ;
return begin ;
}
q = begin ;
while ( q != NULL )
{
if ( q -> info == item_pos )
{
temp = new struct node ;
temp -> info = data_element ;
temp -> prev_node = q -> prev_node ;
temp -> next_node = q ;
q -> prev_node -> next_node = temp ;
q -> prev_node = temp ;
return begin ;
}
q = q -> next_node ;
}
cout << item_pos << " not present in the list\n" ;
return begin ;
}
struct node * deletenode ( struct node * begin , int data_element )
{
struct node * temp ;
if ( begin == NULL )
{
cout << "List is empty\n" ;
return begin ;
}
if ( begin -> next_node == NULL )
if ( begin -> info == data_element )
{
temp = begin ;
begin = NULL ;
delete ( temp ) ;
return begin ;
}
else
{
cout << "Element " << data_element << " not found\n" ;
return begin ;
}
if ( begin -> info == data_element )
{
temp = begin ;
begin = begin -> next_node ;
begin -> prev_node = NULL ;
delete ( temp ) ;
return begin ;
}
temp = begin -> next_node ;
while ( temp -> next_node != NULL )
{
if ( temp -> info == data_element )
{
temp -> prev_node -> next_node = temp -> next_node ;
temp -> next_node -> prev_node = temp -> prev_node ;
delete ( temp ) ;
return begin ;
}
temp = temp -> next_node ;
}
if ( temp -> info == data_element )
{
temp -> prev_node -> next_node = NULL ;
delete ( temp ) ;
return begin ;
}
cout << "Element " << data_element << " not found\n" ;
return begin ;
}
struct node * reverselist ( struct node * begin )
{
if ( begin == NULL )
{
cout << "List is empty\n" ;
return begin ;
}
struct node * p1 , * p2 ;
p1 = begin ;
p2 = p1 -> next_node ;
p1 -> next_node = NULL ;
p1 -> prev_node = p2 ;
while ( p2 != NULL )
{
p2 -> prev_node = p2 -> next_node ;
p2 -> next_node = p1 ;
p1 = p2 ;
p2 = p2 -> prev_node ;
}
begin = p1 ;
cout << "List reverselistd\n" ;
return begin ;
}
|
Output
输出量
If you have any doubts regarding above doubly linked list in C and C++ tutorial then comment below.
如果您对上面的C和C ++教程中的双向链表有任何疑问，请在下面评论。
翻译自: https://www.thecrazyprogrammer.com/2015/09/doubly-linked-list-in-c-and-cpp.html
c语言+双向循环链表