Data structure - single chain table

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
using namespace std;
#define Status int
#define ElemType int
//Single link table node data structure
typedef struct LNode
{
    ElemType data;//Data domain
    struct LNode *next;//Pointer domain
} LNode,*LinkList;
//**************************Basic operation function***************************//
//Initialization function
Status InitList(LinkList &L)
{
    L = new LNode;//Generate the header node so that the deletion and other operations do not have to be divided into the first node and others
    L->next = NULL;
    return 1;
}
//There is no data in the header node to obtain the length of single chain table
int ListLength(LinkList L)
{
    LinkList p=L;
    int sum=0;
    while(p)
    {
        sum++;
        p=p->next;
    }
    return sum-1;//Remove the head node
}
//Insert function -- post insert into position I (1 < = I < = length + 1), i.e. position I need not be distinguished after i-1
bool ListInsert(LinkList &L,int i,ElemType e)
{
    LNode* s;
    LinkList p=L;
    int j=0;
    while(p&&(j<i-1))//j refers to the position i-1 or p has jumped out at the end
    {
        p=p->next;
        ++j;
    }
    if(!p||j>i-1)//When I < 1 or I > ListLength (L) + 1, if the insertion position is invalid, ListLength will not be called to improve efficiency
    {
        printf("Invalid insertion position!!!\n");
        return false;
    }
    s=new LNode;
    s->data=e;
    s->next=p->next;
    p->next=s;
    return true;
}
//Delete function delete node at position I, i.e. delete node after i-1
bool ListDelete(LinkList &L,int i)
{
    LNode* s;
    LinkList p=L;
    int j=0;
    LinkList q;
    while(p&&(j<i-1))//j refers to position i-1
    {
        p=p->next;
        ++j;
    }
    if(!(p->next)||j>i-1)//Invalid delete position when i<1 or i>ListLength (L)
    {
        printf("Invalid delete location!!!\n");
        return false;
    }
    q=p->next;
    p->next=q->next;
    free(q);//Release space
    return true;
}
//The search function finds the first node equal to e by value and returns the node pointer, otherwise NULL
LNode *LocateElem(LinkList L,ElemType e)
{
    LNode *p=L;
    while(p&&(p->data!=e))
    {
        p=p->next;
    }
    return p;
}
//**************************Function implementation function**************************//
//Ergodic output function
void PrintList(LinkList L)
{
    LinkList p=L->next;//Jump over node
    if(ListLength(L))
    {
        printf("All elements of the current single chain table:");
        while(p)
        {
            printf("%d ",p->data);
            p=p->next;
        }
        printf("\n");
    }
    else
    {
        printf("Current single chain table is empty!\n");
    }
}
//Insert function call ListInsert to insert
void Insert(LinkList &L)
{
    int place;
    ElemType e;
    bool flag;
    printf("Please enter the location to insert(Starting from 1)And elements:\n");
    scanf("%d%d",&place,&e);
    flag=ListInsert(L,place,e);
    if(flag)
    {
        printf("Insert successfully!!!\n");
        PrintList(L);
    }
}
//Delete function call ListDelete delete
void Delete(LinkList L)
{
    int place;
    bool flag;
    printf("Please enter the location to delete(Starting from 1):\n");
    scanf("%d",&place);
    flag=ListDelete(L,place);
    if(flag)
    {
        printf("Delete successfully!!!\n");
        PrintList(L);
    }
}
//Find function call LocateElem to find
void Search(LinkList L)
{
    ElemType e;
    LNode *q;
    printf("Please enter the value to find:\n");
    scanf("%d",&e);
    q=LocateElem(L,e);
    if(q)
    {
        printf("Find the element!\n");
    }
    else
        printf("Element not found!\n");
}
//menu
void menu()
{
    printf("********1.Post interpolation    Two.delete*********\n");
    printf("********3.lookup    Four.output*********\n");
    printf("********5.Sign out          *********\n");
}
//Main function
int main()
{
    LinkList L;
    int choice;
    InitList(L);
    while(1)
    {
        menu();
        printf("Please enter the menu number:\n");
        scanf("%d",&choice);
        if(choice==5) break;
        switch(choice)
        {
        case 1:
            Insert(L);
            break;
        case 2:
            Delete(L);
            break;
        case 3:
            Search(L);
            break;
        case 4:
            PrintList(L);
            break;
        default:
            printf("Input error!!!\n");
        }
    }
    return 0;
}