小弟的程序运行不过去 哪位帮帮忙啊

#include <stdio.h>
#include <stdlib.h>
#define TYPE struct stu
#define LEN sizeof (struct stu)
    struct stu
        {
          int num;
          int age;
          struct stu *next;
        };
   struct stu *creat(int n)
    {
        struct stu *head,*pf,*pb;
        int i=0;
        for(i=0;i<n;i++)
        {
          pb=(TYPE*) malloc(LEN);
          printf("input Number and  Age/n");
          scanf("%d%d",&pb->num,&pb->age);
          if(i==0)
         pf=head=pb;
          else pf->next=pb;
          pb->next=NULL;
          pf=pb;
        }
        return(head);
    }
   
     main (void)
     {struct stu *creat(void);
       struct stu *ahead;
       printf("input a list:/n");
       ahead=creat(void);

      }
       /*建立链表*/