链表1.0后插法

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

typedef struct student
{
    int num;
    struct student *next;
}Lstudent,*LPstudent;

void InitLink(LPstudent *phead)
{
    Lstudent *ptr,*r;//,加一个指向尾部的指针*r
    *phead=NULL;
    int n;
    printf("please input number of student:\n");
    scanf("%d",&n);
    while(n>0)
    {
        ptr=malloc(sizeof(Lstudent));
        ptr->num=n;
        ptr->next=NULL;
        if(*phead==NULL)
            *phead=ptr;
        else
            r->next=ptr;

            r=ptr;

        printf("please input number of student:\n");
        scanf("%d",&n);

    }
}

void printf_link(Lstudent *ptri)
{
    while(ptri!=NULL)
    {
    printf("%d   ",ptri->num);
    ptri=ptri->next;
    }
}

int main()
{
    LPstudent head;
    InitLink(&head);
    printf_link(head);

}