1.自己实现单向循环链表的功能
//loop_list.c#include"loop_list.h"
//创建单向循环链表
loop_p create_head()
{loop_p H=(loop_p)malloc(sizeof(loop_list));if(H==NULL){printf("空间申请失败\n");return NULL;}H->len=0;H->next=H;return H;
}//创建结点
loop_p create_node(datatype data)
{loop_p new=(loop_p)malloc(sizeof(loop_list));if(new==NULL){printf("空间申请失败\n");return NULL;}new->data = data; return new;
}//输出
void out_put_loop(loop_p H)
{if(H==NULL){printf("入参为空,请检查\n");return;}loop_p p=H->next;while(p!=H){printf("%d->",p->data);p=p->next;}printf("%c",'H');putchar(10);
}//头插
void insert_head(loop_p H,datatype data)
{if(H==NULL){printf("入参为空,请检查\n");return;}loop_p new=create_node(data);new->next=H->next;H->next=new;H->len++;
}//按位置插入
void insert_pos(loop_p H,datatype data,int pos)
{if(H==NULL){printf("入参为空,请检查\n");return;}if(pos<=0||pos>H->len+1){printf("位置不合理\n");return;}loop_p p=H;for(int i=0;i<pos-1;i++){p=p->next;}loop_p new=create_node(data);new->next=p->next;p->next=new;H->len++;
}//尾删
void del_tail(loop_p H)
{if(H==NULL){printf("入参为空,请检查\n");return;}loop_p p=H;while(p->next->next!=H){p=p->next;}loop_p del=p->next;p->next=p->next->next;free(del);H->len--;
}//按位置删除
void del_pos(loop_p H,int pos)
{if(H==NULL){printf("入参为空,请检查\n");return;}if(pos<=0||pos>H->len){printf("位置不合理\n");return;}loop_p p=H;for(int i=0;i<pos-1;i++){p=p->next;}loop_p del=p->next;p->next = p->next->next;free(del);H->len--;
}
//loop_list.h#ifndef __LOOP_LIST_H__
#define __LOOP_LIST_H__
#include<stdio.h>
#include<string.h>
#include<stdlib.h>typedef int datatype;
typedef struct loop_list
{union{int len;datatype data;};struct loop_list *next;
}loop_list,*loop_p;//创建单向循环链表
loop_p create_head();
//创建结点
loop_p create_node(datatype data);
//输出
void out_put_loop(loop_p H);
//头插
void insert_head(loop_p H,datatype data);
//按位置插入
void insert_pos(loop_p H,datatype data,int pos);
//尾删
void del_tail(loop_p H);
//按位置删除
void del_pos(loop_p H,int pos);#endif
//main.c#include"loop_list.h"
int main(int argc, const char *argv[])
{loop_p H=create_head();insert_head(H,89); insert_head(H,55); insert_head(H,7);out_put_loop(H);insert_pos(H,12,2);out_put_loop(H);del_tail(H);out_put_loop(H);del_pos(H,1);out_put_loop(H);return 0;
}
2.复习前面顺序表和链表的代码，重写链表逆置函数
void overturn_link(link_p H)
{if(H==NULL){printf("入参为空,请检查\n");return;}if(link_empty(H)){printf("链表为空\n");return;}if(H->next->next==NULL){printf("表中只有一个元素,无需翻转\n");return;}link_p p=H->next->next;H->next->next=NULL;link_p q=p->next;while(p!=NULL){p->next=H->next;H->next=p;p=q;if(q!=NULL){q=q->next;}}
}
