在前文实现单向链表的基本操作下,本文实现双向链表的基本操作.

双向链表与单链表差异,是双向链表结点中有前向指针和后向指针.所以在插入和删除新结点元素时候不见要考虑后向指针还要考虑前向指针.

以下是双向链表的C代码:

1 #include
     
        2   3 typedef struct node  4 {  5     int data;  6     struct node *next;  7     struct node *prior  8 }Node;  9  10 //链表的初始化 11 Node* InitList(int number) 12 { 13     int i; 14     Node *pHead=(Node *)malloc(sizeof(Node)); 15     Node *TempHead=pHead; 16     Node *Head=pHead; 17     Head->prior=NULL; 18     int data; 19     for(i=0;i
      
       data=data; 25         pHead->next=NULL; 26         pHead->prior=TempHead; 27         TempHead->next=pHead; 28         TempHead=pHead; 29     } 30     return Head; 31 } 32  33 //显示链表 34 void ShowList(Node *Head) 35 { 36  37     Head=Head->next; 38     while(Head->next!=NULL) 39     { 40         printf("%d ",Head->data); 41         Head=Head->next; 42     } 43     printf("%d",Head->data); 44     printf("\n"); 45 } 46  47 //输出链表某个值的位置 48 int ListLocation(Node *Head,int data,int number) 49 { 50     Node *TempNode=Head; 51     int location=1; 52     TempNode=TempNode->next; 53     while(TempNode->next!=NULL) 54     { 55         if(TempNode->data==data) 56             { 57                 return location; 58             } 59             location++; 60             TempNode=TempNode->next; 61     } 62     if(location>=number) 63         printf("Not found!"); 64 } 65  66 //输出链表某个位置的值 67 int ListData(Node *Head,int location,int number) 68 { 69     if(location>number) 70         printf("Not found!"); 71  72     Node *TempNode=Head; 73     TempNode=TempNode->next; 74     int i; 75     for(i=1;i<=number;i++) 76     { 77         if(location==i) 78             return TempNode->data; 79         TempNode=TempNode->next; 80     } 81 } 82  83 //头入法插入元素 84 void HeadInsertData(Node *Head,int data) 85 { 86     Node *InsertNode=(Node *)malloc(sizeof(Node)); 87     InsertNode->data=data; 88     InsertNode->next=Head->next; 89     Head->next->prior=InsertNode; 90     Head->next=InsertNode; 91     InsertNode->prior=Head; 92 } 93  94 //尾入插入除元素 95 void TailInsertData(Node *Head,int data) 96 { 97     Node *TempNode=Head; 98     Node *DeleteNode=(Node *)malloc(sizeof(Node)); 99     DeleteNode->data=data;100     while(TempNode->next!=NULL)101         TempNode=TempNode->next;102 103     TempNode->next=DeleteNode;104     DeleteNode->next=NULL;105     DeleteNode->prior=TempNode;106 107     free(DeleteNode);108 }109 110 111 112 //删除头结点113 void HeadDeleteData(Node *Head)114 {115     Head->next=Head->next->next;116     Head->next->prior=Head;117 }118 119 120 //删除尾结点121 void TailDeleteData(Node *Head)122 {123     Node *TempNode=Head;124     while(Head->next->next!=NULL)125         Head=Head->next;126 127     Head->next=NULL;128     Head->next->prior=NULL;129 }130 131 int main()132 {133     Node *Head;134     int number;135     printf("Please input the node number:\n");136     scanf("%d",&number);137     Head=InitList(number);138     printf("The initital list is:\n");139     ShowList(Head);140 141     int flag;142     printf("\n\n");143     printf("**********************Your Choice********************\n");144     printf("****************1-输出链表某个值的位置***************\n");145     printf("****************2-输出链表某个位置的值***************\n");146     printf("****************3-头入法插入元素*********************\n");147     printf("****************4-尾入法插入元素*********************\n");148     printf("****************5-删除头结点*************************\n");149     printf("****************6-删除尾结点*************************\n");150     printf("****************0-退出*******************************\n");151     printf("\n\n");152     printf("Please input flag:\n");153     scanf("%d",&flag);154 155     switch(flag)156     {157         case 1:158         {159             int data;160             printf("Please input the data you want locate:\n");161             scanf("%d",&data);162             int location;163             location=ListLocation(Head,data,number);164             printf("The data's location is: %d",location);165             break;166         }167         case 2:168         {169             int location;170             printf("Please input the location you want  data:\n");171             scanf("%d",&location);172             int data;173             data=ListData(Head,location,number);174             printf("The location's data is: %d\n",data);175             break;176         }177         case 3:178         {179             int data;180             printf("Please input the data you want insert in head:\n");181             scanf("%d",&data);182             HeadInsertData(Head,data);183             ShowList(Head);184             break;185         }186         case 4:187         {188             int data;189             printf("Please input the data you want insert in tail:\n");190             scanf("%d",&data);191             TailInsertData(Head,data);192             ShowList(Head);193             break;194         }195         case 5:196         {197             HeadDeleteData(Head);198             ShowList(Head);199             break;200         }201         case 6:202         {203             TailDeleteData(Head);204             ShowList(Head);205             break;206         }207         case 7:208         {209            printf("You choose to exit.\n");210            break;211         }212     }213     return 0;214 }
      
     

 

结果图: