一个链表建立删除的有关问题,请大家帮小弟我看看哪错了

一个链表建立删除的问题,请大家帮我看看哪错了
#include<stdio.h>
#include<stdlib.h>
struct student
{
char name[20];
float num;
char sex;
int age;
struct student *next;
};

struct student *creat(int n)
{
int i;
struct student *head, *p1, *p2;
head = (struct student*)malloc(sizeof(struct student));
head->next = NULL;
p2 = head;
printf("input the name,num,sex,age.\n");
for(i = 1; i <= n; i++)
{
p1 = (struct student*)malloc(sizeof(struct student));
scanf("name:%s,num:%f,sex:%c,age:%d",p1->name,&p1->num,&p1->sex,&p1->age);
p2->next = p1;
p1->next = NULL;
}
return (head);
}

void Del_Elem(struct student *head, int age)
{
struct student *p1,*p2;
p1 = head;
while((p1->age != age)&&(p1->next != NULL))
{
p2 = p1;
p1 = p1->next;
}
if(age == p1->age)
{
if(p1 == head)
{
head->next = p1->next;
}
else
p2->next = p1->next;
printf("the student of age %i is delete.\n",age);
free(p1);
}
else
printf("he is not exist\n");
}
void display(struct student *head)
{
struct student *p;
p = head;
do
{
printf("name:%s,num:%f,sex:%c,age:%d", p->name, p->num, p->sex, p->age);
p = p->next;
}while(p->next != NULL);
}
int main()
{
struct student *creat(int n);
void Del_Elem(struct student *head, int age);
void display(struct student *head);
struct student *head;
int n = 5;
head = creat(n);
display(head);
Del_Elem(head, 20);
display(head);
return 0;
}

出现两个错误
LIBCD.lib(wincrt0.obj) : error LNK2001: unresolved external symbol _WinMain@16
Debug/linklist.exe : fatal error LNK1120: 1 unresolved externals

是新手~不太明白~~帮帮忙看一下了~~

[解决办法]
逻辑修改了一下，修改的地方就不一一解释了，你自己比较看看吧：

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

struct student 
{ 
char name[20]; 
float num; 
char sex; 
int age; 
struct student *next; 
}; 

struct student *creat(int n) 
{ 
int i; 
struct student *head, *p1, *p2; 
head = (struct student*)malloc(sizeof(struct student)); 
head->next = NULL; 
p2 = head; 
printf("input the name,num,sex,age.\n"); 
scanf("%s %f %c %d",head->name,&head->num,&head->sex,&head->age); 

for(i = 1; i <= n-1; i++) 
{ 
p1 = (struct student*)malloc(sizeof(struct student)); 
p1->next = NULL; 

scanf("%s %f %c %d",p1->name,&p1->num,&p1->sex,&p1->age); 
p2->next = p1; 
p2 = p2->next;
} 
return (head); 
} 

struct student *Del_Elem(struct student *head, int age) 
{ 
struct student *p1,*p2; 
p1 = head; 
while( p1 != NULL && p1->age != age ) 
{ 
p2 = p1; 
p1 = p1->next; 
}

if( p1 != NULL && age == p1->age) 
{ 
if(p1 == head) 
head = p1->next;
else 
p2->next = p1->next;
printf("the student of age %i is delete.\n",age); 
free(p1); 
} 
else 
{
printf("he is not exist\n"); 
}

return head;
} 

void display(struct student *head) 

{ 
struct student *p; 
p = head; 
while( p != NULL ) 
{
printf("name:%s,num:%f,sex:%c,age:%d\n", p->name, p->num, p->sex, p->age); 
p = p->next;
}
} 

int main() 
{ 
struct student *creat(int n); 
struct student *Del_Elem(struct student *head, int age);
void display(struct student *head); 
struct student *head; 
int n = 5; 
head = creat(n); 
display(head); 
head = Del_Elem(head, 20); 
display(head); 
return 0; 
}
[解决办法]

C/C++ code

#include <stdio.h>#include <stdlib.h>struct student{  char name[20];  int num;  short sex;  int age;  struct student *next;};struct student *creat(int n){  int i;  struct student *head, *p1, *p2;  printf("input the name,num,sex,age.\n");  head = (struct student*)malloc(sizeof(struct student));  scanf("%s%d%d%d",head->name,&head->num,&head->sex,&head->age);  head->next = NULL;  p2 = head;  for(i = 1; i < n; i++)    {      p1 = (struct student*)malloc(sizeof(struct student));      scanf("%s%d%d%d",p1->name,&p1->num,&p1->sex,&p1->age);      p2->next = p1;      p1->next = NULL;      p2=p1; // let p2 point to p1    }  return (head);}void Del_Elem(struct student **head, int age)//we may change the head so we use **{  struct student *p1,*p2;  p1 = *head;  while((p1->age != age)&&(p1->next != NULL))    {      p2 = p1;      p1 = p1->next;    }  if(age == p1->age)    {      if(p1 == *head)        {         *head = p1->next;//let head point to the next        }      else        p2->next = p1->next;      printf("the student of age %i is delete.\n",age);      free(p1);    }  else    printf("he is not exist\n");}void display(struct student *head){  struct student *p;  p = head;  do    {      printf("name:%s,num:%d,sex:%c,age:%d\n", p->name, p->num, (p->sex>0)?'f':'m' , p->age);      p = p->next;    }while(p != NULL);//p already point to the next now}struct student *creat(int n);void Del_Elem(struct student **head, int age);void display(struct student *head);int main(){  struct student *head;  int n = 5;  head = creat(n);  display(head);  Del_Elem(&head, 22);  display(head);  return 0;}