刚刚学习单链表，自己试着写了一个跟书上有点不同，求指出有什么缺点

#include <iostream>
using namespace std;
typedef struct link
{
    int data;
    link *next;
}llist;
llist *head()
{
    llist *r,*s,*head;
    head = new link;
    r = new link;
    s = new link;
    int x;
    head->next = r;
    cout << "please input something:";
    cin >> x;
    while(x!=0)
    {
        r->data = x;
        r->next = s;
        r=s;
    }
    r->next = NULL ;
    return head;
}