循环链表

  1 #include <stdio.h>
  2 #include <stdlib.h>
  3 
  4 typedef struct CLNode{
  5     int data;
  6     struct CLNode* next;
  7 }CLNode, *CLinkList;
  8 
  9 //产生空的双向循环链表
 10 void InitCL(CLinkList CL){
 11     if(CL != NULL){
 12         CL->next = CL;
 13     }
 14     else{
 15         CL = (CLinkList)malloc(sizeof(CLNode));
 16     }
 17 }
 18 
 19 //在CL的头结点插入元素
 20 void InsertFront(CLinkList CL, int value){
 21     CLinkList p;
 22     p = (CLinkList)malloc(sizeof(CLNode));
 23     p->data = value;
 24     p->next = CL->next;
 25     CL->next = p;
 26 }
 27 
 28 //在CL的尾结点插入元素
 29 void InsertEnd(CLinkList CL, int value){
 30     CLinkList p, q;
 31     p = (CLinkList)malloc(sizeof(CLNode));
 32     p->data = value;
 33     q = CL;
 34     while(q->next != CL){
 35         q = q->next;
 36     }
 37     p->next = q->next;
 38     q->next = p;
 39 }
 40 
 41 //打印CL
 42 void Print(CLinkList CL){
 43     CLinkList p;
 44     p = CL->next;
 45     while(p != CL){
 46         printf("%d\t", p->data);
 47         p = p->next;
 48     }
 49     printf("\n");
 50 }
 51 
 52 //删除CL的头结点
 53 void DeleteFront(CLinkList CL, int *val){
 54     CLinkList p;
 55     p = CL->next;
 56     if(p != CL){
 57         CL->next = p->next;
 58         *val = p->data;
 59     }
 60     else{
 61         printf("LinkList is empty!\n");
 62     }
 63 }
 64 
 65 //删除CL的尾节点
 66 void DeleteEnd(CLinkList CL, int *val){
 67     CLinkList p, q;
 68     q = CL;
 69     p = CL->next;
 70     if(p != NULL){
 71         while(p->next != CL){
 72             q = p;
 73             p = p->next;
 74         }
 75         *val = p->data;
 76         q->next = p->next;
 77     }
 78     else{
 79         printf("LinkList is empty!\n");
 80     }
 81 }
 82 
 83 int main(){
 84     CLinkList ML;
 85     int i, res;
 86     ML = (CLinkList)malloc(sizeof(CLNode));
 87     InitCL(ML);
 88     DeleteFront(ML, &res);
 89     DeleteEnd(ML, &res);
 90     for(i = 1; i <= 8; i++){
 91         InsertFront(ML, i + 38);
 92         InsertEnd(ML, i + 100);
 93     }
 94     Print(ML);
 95     DeleteFront(ML, &res);
 96     printf("%d is deleted from linklist.\n", res);
 97     DeleteEnd(ML, &res);
 98     printf("%d is deleted form linklist.\n", res);
 99     Print(ML);
100     printf("hello world!\n");
101     return 0;
102 }