各种基本算法实现小结（一）—— 链 表

各种基本算法实现小结（一）—— 单链表

（均已测试通过）

 

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单链表(测试通过)   

测试环境： Win-TC

 #include <stdio.h>
 #include <stdlib.h>
 struct _node
 {
     int data;
     struct _node *next;
 };
 typedef struct _node list;
 void display(list *l)
 {
     list *p;
     p=l;
     while(p->next)
     {
         printf("%5d", p->next->data);
         p=p->next;
     }
 }
 int main()
 {
     int i, n;
     list *h, *p, *s;
     printf("Enter num n:");
     scanf("%d", &n);
     h=(list*)malloc(sizeof(list));
     h->data=-1;
     h->next=NULL;
     s=p=h;
     for(i=n;i>0;i--)
     {
         p=(list*)malloc(sizeof(list));
         scanf("%d", &(p->data));
         p->next=h->next;
         h->next=p;
         h=h->next;
     }
     display(s);
     return 0;
 }

 

运行结果：

 

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单链表各种操作(测试通过)   

测试环境： Win-TC

 #include <stdio.h>
 #include <malloc.h>
 #include <stdlib.h>
 struct _node
 {
     int data;
     struct _node *next;
 };
 typedef struct _node node, *plist;
 plist init_list()
 {
     plist pl;
     pl=(plist)malloc(sizeof(node));
     if(NULL==pl)
     {
         printf("init list,  malloc is fail...\n");
         return NULL;
     }
     pl->data=-1;
     pl->next=NULL;
     return pl;
 }
 int isempty_list(plist pl)
 {
     if(NULL==pl || NULL!=pl->next)
         return 1;
     else
         return 0;
 }
 plist clear_list(plist pl)
 {
     pl=NULL;
     return pl;
 }
 void destroy_list(plist pl)
 {
     plist p, s;

     p=pl->next;
     while(p)
     {
         s=p;
         p=p->next;
         free(s);
     }

     pl=NULL;
 }
 void insert_item(plist pl, int i, int e)
 {
     int j=1;
     plist p, s;
     p=pl;
     while(p && j<i)
     {
         p=p->next;
         j++;
     }
     if(!p || j>i)  /* >len or <1  */
         printf("Insert fail...\n");
     s=(plist)malloc(sizeof(node));
     s->data=e;
     s->next=p->next;
     p->next=s;
 }
 void display(plist pl)
 {
     plist p;
     p=pl->next;
     while(pl && p)
     {
         printf("%5d", p->data);
         p=p->next;
     }
     printf("\n\n");
 }
 int getbyid_item(plist pl, int i)
 {
     plist p=pl->next;
     int j=1;
     while(p && j<i)
     {
         p=p->next;
         j++;
     }
     if(!p || j>i)  /* >len or <1  */
     {
         printf("fail...\n");
         exit(1);
     }
     return p->data;
 }
 int locate_item(plist pl, int e)
 {
     plist p=pl->next;
     int j=1;
     while(p->data != e && p->next)
     {
         p=p->next;
         j++;
     }
     if(p->data == e)
         return j;
     else
     {
         printf("There is n %d in list\n", e);
         return -1;
     }
 }
 void delete_item(plist pl, int i, int *e)
 {
     plist p=pl;
     plist q;
     int j=1;
     while(p->next && j<i)
     {
         p=p->next;
         j++;
     }
     if(!p->next || j>i)  /* >len or <1  */
     {
         printf("fail....\n");
         return;
     }
     q=p->next;
     p->next=q->next;
     *e=q->data;
     free(q);
 }
 int len_list(plist pl)
 {
     int j=0;
     plist p=pl;
     while(pl && p->next)
     {
         j++;
         p=p->next;
     }
     return j;
 }
 plist traverse_list(plist pl)
 {
     plist h, p, s;

     if(!pl || !pl->next)
         return pl;
     h=pl->next;
     s=h;
     p=s->next;
     h->next=NULL;
     while(p)
     {
         s=p;
         p=p->next;
         s->next=h;
         h=s;
     }
     pl->next=h;

     return pl;
 }
 int main()
 {
     int len, pos, *del;
     plist pl=NULL;
     del=(int *)malloc(sizeof(int));
     pl=init_list();
     isempty_list(pl);
     insert_item(pl, 1, 1);
     insert_item(pl, 2, 3);
     insert_item(pl, 3, 5);
     insert_item(pl, 4, 7);
     insert_item(pl, 5, 9);
     insert_item(pl, 6, 11);
     display(pl);
     len=len_list(pl);
     printf("link list len: %d\n", len);
     pos=locate_item(pl, 7);
     printf("num 7 pos: %d\n", pos);
     delete_item(pl, 3, del);
     printf("delete pos 3 num: %d\n", *del);
     display(pl);
     printf("link list traverse...\n");
     pl=traverse_list(pl);
     display(pl);
     destroy_list(pl);
     return 0;
 }

运行结果：

 

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单向循环链表(测试通过)   

测试环境： Win-TC

 #include <stdio.h>
 #include <malloc.h>
 struct _node
 {
     int data;
     struct _node *next;
 };
 typedef struct _node node, *plist;
 plist init_list()
 {
     plist pl=(plist)malloc(sizeof(node));
     if(!pl)
     {
         printf("error malloc fail...\n");
         return NULL;
     }
     pl->data=-1;
     pl->next=pl;    /* pl->next=NULL */
     return pl;
 }
 void insert_item(plist pl, int pos, int data)
 {
     int j=0;
     plist p,s;
     s=p=pl;
     while(p && j<pos-1)
     {
         p=p->next;
         j++;
     }
     if(!p || j>pos-1)
     {
         printf("Error insert fail...\n");
         return;
     }
     s=(plist)malloc(sizeof(node));
     if(!s)
     {
         printf("Error malloc fail...\n");
         return;
     }
     s->data=data;
     s->next=p->next;
     p->next=s;
 }
 int find_item(plist pl, int data)
 {
     plist s,p;
     s=p=pl;
     p=p->next;
     while(s != p)
     {
         if(data==p->data)
             return 1;
         p=p->next;
     }
     return 0;
 }
 void delete_item(plist pl, int data)
 {
     plist p,s;
     s=p=pl;
     if(data == p->data) /* first item is equal with data, then last item = second item */
     {
         s=p;
         while(s != p->next)
             p=p->next;
         p->next=s->next;
         return;
     }
     while(s != p->next) /* first item is not equal with data */
     {
         if(data == p->next->data)
         {
             p->next=p->next->next;
             return;
         }
         p=p->next;
     }
 }
 void display(plist pl)
 {
     plist s,p;
     s=p=pl;
     printf("%5d", p->data); /* print first item */
     p=p->next;
     while(s != p)
     {
         printf("%5d", p->data);
         p=p->next;
     }
     printf("\n\n");
 }
 int main()
 {
     int f;
     plist pl;
     pl=init_list();
     insert_item(pl, 1, 1);
     insert_item(pl, 2, 3);
     insert_item(pl, 3, 5);
     insert_item(pl, 4, 7);
     insert_item(pl, 5, 9);
     display(pl);
     printf("Finding 3...\n");
     f=find_item(pl, 3);
     if(f)
         printf("True find 3\n");
     else
         printf("False find 3...\n");
     printf("\nDeleting 1...\n");
     delete_item(pl->next, 1);
     display(pl->next);
     return 0;
 }

运行结果：

 

=================================================

双向循环链表(测试通过)   

测试环境： Win-TC

 #include <stdio.h>
 #include <malloc.h>
 struct _node
 {
     int data;
     struct _node *prior;
     struct _node *next;
 };
 typedef struct _node node, *plist;
 plist init_list()
 {
     plist p;
     p=(plist)malloc(sizeof(node));
     if(!p)
     {
         printf("Error, malloc fail...\n");
         return NULL;
     }
     p->data=-1;   /* head->data = -1 */
     p->prior=p;
     p->next=p;
     return p;
 }
 void insert_item(plist pl, int pos, int data)
 {
     int j=0;
     plist s,p;
     p=pl;
     while(p && j<pos-1)
     {
         p=p->next;
         j++;
     }
     if(!p || j>pos-1) /* pos is less than 1 or pos larger than len_list+1 */
     {
         printf("Error %d is invalide num...\n", pos);
         return;
     }
     s=(plist)malloc(sizeof(node));
     if(!s)
     {
         printf("Error, malloc fail...\n");
         return;
     }
     s->data=data;
     s->prior=p;
     s->next=p->next;
     p->next->prior=s;
     p->next=s;
 }
 int find_item(plist pl, int data)
 {
     plist s,p;
     s=p=pl;
     if(data == p->data)
         return 1;
     p=p->next;
     while(s != p)
     {
         if(data == p->data)
             return 1;
         p=p->next;
     }
     return 0;
 }
 void delete_item(plist pl, int data)
 {
     plist s,p;
     s=p=pl;
     if(data == p->data) /* first check equal */
     {
         p->prior->next=p->next;
         p->next=p->prior;
         return;
     }
     while(s != p->next)
     {
         if(data == p->next->data)
         {
             p->next=p->next->next;
             p->next->next->prior=p;
         }
         p=p->next;
     }
 }
 void display(plist pl)
 {
     plist s,p;
     s=p=pl;
     printf("%5d", p->data);  /* first item, such as head->data is -1 */
     p=p->next;
     while(s != p)
     {
         printf("%5d", p->data);
         p=p->next;
     }
     printf("\n\n");
 }
 int main()
 {
     int f;
     plist pl;
     pl=init_list();
     insert_item(pl, 1, 1);
     insert_item(pl, 2, 3);
     insert_item(pl, 3, 5);
     insert_item(pl, 4, 7);
     insert_item(pl, 5, 9);
     display(pl);
     printf("Finding 3...\n");
     f=find_item(pl->next->next, 3);
     if(f)
         printf("True find 3\n");
     else
         printf("Fail find 3...\n");
     printf("Finding 6...\n");
     f=find_item(pl->prior->prior, 6);
     if(f)
         printf("True find 6\n");
     else
         printf("Fail find 6...\n");
     printf("\nDeleting 3...\n");
     delete_item(pl->next->next, 3);
     display(pl);
     return 0;
 }

运行结果：

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以上代码，均在Win-TC 1.9.1 编译器环境测试通过（测试部分用例）

由于刚刚学习算法，编程水平有限，以上代码多有考虑不周或错误

欢迎大家在下面留言，改正或优化代码，给予指点或建议，谢谢！

参考推荐：

学习算法之路

各种基本算法实现小结（一）—— 链 表

各种基本算法实现小结（二）—— 堆 栈

各种基本算法实现小结（三）—— 树与二叉树

各种基本算法实现小结（四）—— 图及其遍历

各种基本算法实现小结（五）—— 排序算法

各种基本算法实现小结（六）—— 查找算法

各种基本算法实现小结（七）—— 常用算法

12个有趣的C语言面试题

作者原文地址：http://blog.csdn.net/sunboy_2050/article/details/5640326