数据结构趣题——动态双向链表的使用

   1: #include <stdio.h>

   2: #include <stdlib.h>

   3:  

   4: typedef struct node {

   5:     int data;

   6:     int freq;

   7:     struct node *prior;

   8:     struct node *next;

   9: } dbLNode, *dbLinkList;

  10:  

  11: /*创建一个双向链表，返回它的头指针*/

  12: dbLinkList GreatdbLinkList(int n) {

  13:     dbLinkList p, r, list = NULL;

  14:     int e;

  15:     int i;

  16:     list = (dbLinkList)malloc(sizeof(dbLNode));  /*创建头结点head,头结点中不存放内容*/

  17:     list->next = list->prior = NULL;

  18:  

  19:     for(i = 1; i <= n; i++) {

  20:         scanf("%d", &e);

  21:         p = (dbLinkList)malloc(sizeof(dbLNode));

  22:         p->data = e;

  23:         p->freq = 0;

  24:         p->next = NULL;

  25:         p->prior = NULL;

  26:  

  27:         if(!list->next) {

  28:             list->next = p;      /*第一个结点*/

  29:             p->prior = list;

  30:         }

  31:         else {

  32:             r->next = p;   /*双向连接下面的结点*/

  33:             p->prior = r;

  34:         }

  35:  

  36:         r = p;

  37:     }

  38:  

  39:     return list;

  40: }

  41:  

  42: /*访问双向链表中指定的结点，并调整结点次序*/

  43: void visit(dbLinkList *l, int x) {

  44:     dbLinkList p = *l, q, r, s;

  45:     p = p->next;   /*p指向第一个结点*/

  46:  

  47:     while(p->data != x && p != NULL)p = p->next;

  48:  

  49:     if(p == NULL) {

  50:         printf("Input error!\n");

  51:         return;

  52:     }

  53:  

  54:     p->freq ++;

  55:     printf("Visiting this node\n");

  56:  

  57:     while((p->prior) != *l && p->freq > p->prior->freq)

  58:     {

  59:  

  60:         /*实现双向链表结点的交换*/

  61:         q = p->prior;

  62:         r = p->next;

  63:         s = p->prior->prior;

  64:         p->prior = q->prior;

  65:         p->next = q;

  66:         q->prior = p;

  67:         q->next = r;

  68:         r->prior = q;

  69:         s->next = p;

  70:     }

  71:  

  72: }

  73:  

  74: void TransdbLinkList(dbLinkList l)

  75: {   /*遍历整个双向链表,并打印出每个结点中的数据和访问频度*/

  76:     l = l->next;

  77:  

  78:     while(l != NULL) {

  79:         printf("(data:%d ,freq:%d)--> ", l->data, l->freq);

  80:         l = l->next;

  81:     }

  82:  

  83:     printf("X\n\n");

  84:  

  85: }

  86:  

  87: int main()

  88: {

  89:     dbLinkList l;

  90:     int d;

  91:     printf("Input five integer to creat a doubly link list\n");

  92:     l = GreatdbLinkList(5);

  93:     TransdbLinkList(l);

  94:  

  95:     printf("Please input the data that you want to vist\n");

  96:  

  97:     scanf("%d", &d);

  98:  

  99:     while(d != 0) {

 100:         visit(&l, d);

 101:         TransdbLinkList(l);

 102:         scanf("%d", &d);

 103:     }

 104:     return 0;

 105: }

 106: