题目是这样的

链表操作：
利用链表的插入运算建立线性链表，然后利用链表的查找、删除、计数、输出等运算反复实现链表的这些操作（插入、删除、查找、计数、输出单独写成函数的形式），并能在屏幕上输出操作前后的结果。
   我写了程序就是用TC不能运行！还有我写的对不对！~谁帮我看下啊！谢谢。。

      #include<stdio.h>
#include<malloc.h>
#include<string.h>
#define null 0
struct node/* The struct for the information of a student. */
{int num;
char name[8];
float score;
struct node *next;
};
typedef struct node node;
node *findnum(node *head,int snum) /* Finding the needed num from the database*/
{ node *t;
t=head->next;
while(t&&(t->num!=snum))
t=t->next;
return t;
}
node *findname(node *head,char s[]) /* Finding the needed name from the database*/
{node *t;
t=head->next;
while(t&&strcmp(t->name,s))
t=t->next;
return t;
}
void findnumout(node *head,int snum)/*Find the record according to num and print it out*/
{node *t;int sign=1;
t=head->next;
puts("\nFinding:");
while(t)
{if(t->num==snum)
{printf("The student you want to find:  num:%d,name:%s,score:%f\n",t->num,t->name,t->score);
sign=0;
}
t=t->next;
}
if(sign)
puts("It is wrong!Not find!\n");
}
void findnameout(node *head,char s[])/*Find the record according to name and print it out*/
{node *t;int sign=1;
t=head->next;
puts("\nNow it is finding:");
while(t)
{if(!strcmp(t->name,s))
{printf("The student you want to find:  num:%d,name:%s,score:%f\n",t->num,t->name,t->score);
sign=0;
}
t=t->next;
}
if(sign)
puts("It is wrong!Not find!\n");
}
node *findp(node *head,node *sp)
{node *t;
t=head;
while(t&&t->next!=sp)
t=t->next;
return t;
}
node *creatnode()   /* Creating a database .It is a linked-list with a header */
{node *head,*t,*p;char c;/* When the "name" received comes to "0",the creation is over.*/
head=(node*)malloc(sizeof(node));
head->next=null;
t=head;
p=(node*)malloc(sizeof(node));
p->next=null;
puts("Input the num:");
scanf("%d",&p->num);
puts("Input the name:(within 8 words)");
scanf("%s",p->name);c=getchar();
puts("Input the score:");
scanf("%f",&p->score);
while(p->name[0]!='0')/*The "name" equal to "0" stands for the creation-finished sign.*/
{t->next=p;p->next=null;
t=t->next;
p=(node*)malloc(sizeof(node));
puts("Input the num:");
scanf("%d",&p->num);
puts("Input the name:(within 8 words)");
scanf("%s",p->name);c=getchar();
puts("Input the score:");
scanf("%f",&p->score);
}
return head;
}
void insert(node *head,int snum)/* Inserting a record into the database. */
{node *p,*t;char c; /* The function inserts the record into the database according to "num". */
p=(node*)malloc(sizeof(node));
p->next=null;
t=findnum(head,snum); /* Find the record whose "num" equals to "snum".*/
puts("Inserting!\n");
puts("Input the num:");
scanf("%d",&p->num);
puts("Input the name:(within 8 words)");
scanf("%s",p->name);c=getchar();
puts("Input the score:");
scanf("%f",&p->score);
if(t)
{if(t->next!=null)
  {p->next=t->next;t->next=p;}
else
  t->next=p;
}
else puts("\nIt is wrong!\n");
}
void deletenode(node *head,int snum)/* Deleting a record from the database. */
{node *t;                      /*The function deletes the record according to "num". */
t=head;
while(t->next&&(t->next->num!=snum))/*Find the previous record of the "snum"-record */
t=t->next;
if(t->next)
t->next=t->next->next;
else puts("\nIt is wrong!\n");
}
void print(node *head)     /* Printing all the records. */
{node *t;t=head->next;
while(t)
{printf("The num:%d,name:%s,score:%f\n",t->num,t->name,t->score);t=t->next;}
free(t);
}
void sortnum(node *head)/*Sort all the nodes using the algorithm of bubble*/
{node *a,*b;int sign;   /*According to the nums */
while(a)
{a=head->next;
b=a->next;
sign=1;
while(b)
{if(a->num>b->num)
{findp(head,a)->next=b;a->next=b->next;b->next=a;b=a->next;sign=0;
}
else {a=b;b=b->next;}
}
if(sign)
break;
}
}
void sortscore(node *head)/*Sort all the nodes using the algorithm of bubble*/
{node *a,*b;int sign;     /*According to the score */
while(a)
{a=head->next;
b=a->next;
sign=1;
while(b)
{if(a->score>b->score)
{findp(head,a)->next=b;a->next=b->next;b->next=a;b=a->next;sign=0;
}
else {a=b;b=b->next;}
}
if(sign)
break;
}
}
void main()
{node *head;
head=creatnode();
puts("\nPrevious database is:\n");
print(head);
insert(head,12);/*Insert a record after the node whose num is 12*/
printf("After the action of inserting,the database is:\n");
print(head);
deletenode(head,11);/*Delete the record whose num is 11 */
puts("\nHaving been deleted,the database now is:\n");
print(head);
puts("\nTake the action of Sorting according to the num:\n");
sortnum(head);
print(head);
puts("\nTake the action of Sorting according to score:\n");
sortscore(head);
print(head);
findnumout(head,12);/*Check out the student whose num is 12. */
findnameout(head,"huhl");/*Check out the student whose name is huhl */
}