线性表的链式表示和实现（插入删除建空）

#include <iostream>
#include<cstdio>
using namespace std;
typedef struct
{
    int data;
}ElemType;
typedef struct LNode
{
     ElemType elem;
     struct LNode *next;
}LNode,*LinkList;

int GetElem_L(LinkList L, int i, ElemType& e)
{
    LNode *p = L->next;
    int j = 1;
    while (p&&j < i)
    {
        p = p->next;
        ++j;
    }
    if (!p || j>i)
        return 0;
    e = p->elem;
    return 1;
}
int ListInsert_L(LinkList &L, int i, ElemType e)
{
     LNode *p = L->next;
     int j = 1;
     while (p && j < i-1)
     {
         p = p->next;
         ++j;
     }
     if (!p || j>i-1)
         return 0;
     LNode *node =(LNode*)malloc(sizeof(LNode));
     node->elem = e;
     LNode* q = p->next;
     p->next = node;
     node->next = q;
     return 1;
}
int ListDelete_L(LinkList &L, int i, ElemType &e)
{
     LNode *p = L->next;
     int j = 1;
     while (p->next&&j < i - 1)//注意此处为p->next，因为若是p，则出来的p可能为空
     {
         p = p->next;
         ++j;
     }
     if (!p->next || j>i - 1)
         return 0;
     LNode*q= p->next;
     e = q->elem;
     p->next = p->next->next;
     free(q);
     return 1;
}
void CreateList_L(LinkList &L, int n)
{
     printf("Enter the value of the node:");
   // L = (LinkList)malloc(n*sizeof(LNode)); 如果像这样创建的话，
   //那就是生成连续存储空间的线性表，应该单独对每一个节点分配内存空间
     L = (LinkList)malloc(sizeof(LNode));
     L->next = nullptr;//先生成一个表头的单链表
     for (int i = n;i > 0;--i)
     {
          LNode *pnode = (LinkList)malloc(sizeof(LNode));
          scanf("%d",&pnode->elem.data);
          pnode->next = L->next;//插入方式为向表头的后一个插入，不然插在表尾太麻烦
          L->next = pnode;
     }
}
void ShowList(LinkList &L)
{
      LNode *pNode = L->next;
      while (pNode)
      {
          printf("%d  ", pNode->elem.data);
          pNode = pNode->next;
      }
}
int main()
{
     LinkList L;
     cout<<"Enter the length of the linked list:";
     int num;
     cin>>num;
     CreateList_L(L, num);//建表
     ShowList(L);//展示
     ElemType e1,temp;

     cout<<"\nTo increase the number of positions:";
     int place;
     cin>>place;
     cout<<"\nEnter the number to insert:";
     cin>>e1.data;
     ListInsert_L(L, place, e1);
     ShowList(L);

     cout<<"\nThe number of digits to be deleted:";
     int place1;
     cin>>place1;
     ListDelete_L(L, place1, temp);
     ShowList(L);
     printf("\nThe deleted node value is :%d\n", temp.data);
    return 0;
}