单链表的建立、插入、删除

//////////////////////////////////////////
//单链表的初始化、建立、插入、查找、删除
//////////////////////////////////////////

#include <stdio.h>
#include <stdlib.h>

typedef int ElemType;

//定义结点类型
typedef struct Node
{
 

   ElemTypedata;      //单链表的数据域
    struct Node*next;   //单链表的指针域
}Node,*LinkedList;

//单链表的初始化
LinkedList LinkedListInit()
{
    Node *L;
    L = (Node*)malloc(sizeof(Node));   //申请结点空间
   if(L==NULL)            //判断是否有足够的内存空间
    {
      printf("Cannot malloc memory!\n");
    }
   L->next=NULL;            //将next设置为NULL，初始长度为0的单链表
}

//建立单链表  头插法建立单链表
LinkedList LinkedListCreatH()
{
    Node*L;
    L = (Node*)malloc(sizeof(Node));
   L->next=NULL;            //初始化一个空链表

    ElemTypex;             //x为链表数据域中的数据
   while(scanf("%d",&x)!= 0)
    {
       if(x ==0)
         break;          //退出条件
       Node*p;
       p = (Node*)malloc(sizeof(Node));//申请新的结点
      p->data =x;         //结点数据域赋值
      p->next =L->next;      //将结点插入到表头L-->|2|-->|1|-->NULL
      L->next = p;
    }
    returnL;
}

//建立单链表，尾插法建立单链表

LinkedList LinkedListCreatT()
{
    Node*L;
    L = (Node*)malloc(sizeof(Node));
   L->next=NULL;            //初始化一个空链表

    Node*r;
    r =L;               //r始终指向终端结点，开始时指向头结点
    ElemTypex;             //x为链表数据域中的数据
   while(scanf("%d",&x)!=EOF)
    {
       if(x ==0)
         break;          //退出条件
       Node*p;
       p = (Node*)malloc(sizeof(Node));//申请新的结点
      p->data =x;         //结点数据域赋值
      r->next =p;      //将结点插入到表头L-->|1|-->|2|-->NULL
       r = p;
    }
   r->next = NULL;
    returnL;
}

//单链表的插入，在链表的第i个位置插入x的元素
LinkedList LinkedListInsert(LinkedList L,int i,ElemType x)
{
    Node*pre;      //pre为前驱结点
    pre =L;
    int tempi =0;
    for(tempi =1;tempi < i;tempi++)
    {
       pre =pre->next;   //查找第i位置的前驱结点
    }
    Node*p;      //插入结点为p；
    p = (Node*)malloc(sizeof(Node));
   p->data = x;
   p->next = pre->next;
   pre->next = p;
    returnL;
}

//单链表的删除，在链表中删除值为x的元素
LinkedList LinkedListDelete(LinkedList L,ElemType x)
{
    Node*p,*pre;      //pre为前驱结点，p为查找结点
    p =L->next;
   while(p->data!=x)   //查找值为x的元素
    {
       pre =p;
       p =p->next;
    }
   pre->next =p->next;   //删除操作，将其前驱next指向后继
   free(p);
    returnL;
}

int main()
{
    LinkedListlist;
    LinkedListstart;
   printf("please input single linkedlist data:\n");
    list =LinkedListCreatH();
    for(start =list->next;start!=NULL;start =start->next)
      printf("%d",start->data);
   printf("\n");
   
    int i;
    ElemTypex;
   printf("Please enter the location to inseart the data");
   scanf("%d",&i);
   printf("Please enter the value to inseart the data");
   scanf("%d",&x);
   LinkedListInsert(list,i,x);
    for(start =list->next;start!=NULL;start =start->next)
      printf("%d",start->data);
   printf("\n");
   printf("Input the value you want to delete:\n");
   scanf("%d",&x);
   LinkedListDelete(list,x);
    for(start =list->next;start!=NULL;start=start->next)
   printf("%d",start->data);
   printf("\n");
   return  0;
}