简单的通讯录（有bug）

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

#define MAXSIZE 11   //这个最好大一点

typedef struct address_book
{
   // int NO;
    char name[MAXSIZE];
    char num[MAXSIZE];
    struct address_book *next;
}adbook;

#if 1
void create_adbook(adbook *head, int n)    //这个函数不需要返回值的所以返回值可以为void
{
    adbook *p;
    adbook *r;
    int i;
  //  p = (adbook *)malloc(sizeof(adbook));
     r = head;

    for(i = 0; i < n; i++)
    {
        p = (adbook *)malloc(sizeof(adbook));
        printf("please input linkman's name, num\n");
       // scanf("%d,%s,%s",&(p->NO), &(p->name), &(p->num));   //scanf 这样用不好 输入的时候还要自己加逗号

      //  scanf("%d",&(p->NO));
        scanf("%s",p->name);
        scanf("%s",p->num);

        r->next = p;
        r = p;
    }
    r->next = NULL;

  //  return head;
}
#endif

int add(adbook *head, int j)
{
    int i = 0;
    adbook *p;
    adbook *s;

    p = head;
    while(p && i < j )
    {
        p = p->next;
    ++i;
    }

    if(!p || i > j)
    {    
        return -1;
    }
    s = (adbook *)malloc(sizeof(adbook));

    s->next = p->next;
    p->next = s;
    printf("input the name you add:\n" );
    scanf("%s", p->name);
    printf("input the num you add:\n");
    scanf("%s", p->num);

    return 0;
}

int delete(adbook *head,int i)
{
    adbook *p;
    adbook *q;
    int j = 1;
    p = head;
    while(p->next && j < i)
    {
        p = p->next;
    j++;
    }
    if(!(p->next) || j > i)
    {
        return -1;
    }

    q = p->next;
    p->next = q->next;
    free(q);

    return 0;
}

int find(adbook *head, int h)
{
    int j = 0;
    adbook *p;
    p = head;
    while(p  && j < h)
    {
        p = p->next;
    j++;
    }
    if(!p || j > h)
    {
        return -1;
    }

    printf("%s,%s\n", p->name, p->num);
    return 0;
}

void print(adbook *head)
{
    adbook *p;
    p = head;

    p = p->next;

    while(p!= NULL)
    {
        printf(" %s, %s\n", p->name, p->num);
        p = p->next;
    }

}
int main()
{
    int n;
    int k;
    int i;
    int j;
    int h;

    adbook *head;

    head = (adbook *)malloc(sizeof(adbook));
    head->next = NULL;

    printf("This is a empty address book.please add new linkman!\n");
    printf("please input sum(linkman) n = ");
    scanf("%d", &n);

    create_adbook(head, n);

    printf("This address book created success!\n");
    print(head);

    printf("please input the num (1-add,2-delete,3-find):\n");
    scanf("%d", &k);

    switch(k)
    {
        case 1: 
        print(head);
        printf("please input the add num j = ");
        scanf("%d", &j);
        add(head, j);
        print(head);
        break;
    case 2: 
        printf("please input the delete num i = ");
        scanf("%d", &i);
        delete(head,i);
        print(head);
        break;
    case 3: 
        printf("please input the find num h = ");
        scanf("%d", &h);
        find(head, h);
        break;
    default :
        printf("please input again!\n");
    break;
    }

    return 0;
}