#include"stdio.h"
#include<stdlib.h>
#include<string.h>
#include<malloc.h>
struct student
{
 long num;
 char name[20];
 char sex;
 int age;
 struct student *next;
};void print(void);
void display(struct student *head)
{
 struct student *p;
 if(head==NULL)
  printf("這是一個空鏈表！/n");
 else
 {
      printf("學 號    姓        名      性   別    年  齡/n");
  p=head;
  while(p!=NULL)
  {
   printf("%-4ld        %-8s          %-1c         %-2d/n",p->num,p->name,p->sex,p->age);
   p=p->next;
  }
 }
}
struct student *creat()
{
 struct student *head,*p,*q=NULL;
 int n,m;
 printf("請輸入學生人數:");
 scanf("%d",&m);
 head=NULL;
 n=1;
 while(n<=m)
 {
  p=(struct student*)malloc(sizeof(struct student));
  printf("/n請輸入學號：");
  scanf("%ld",&p->num);
  getchar();
  printf("請輸入姓名：");
  scanf("%s",p->name);
  getchar();
  printf("請輸入性別：");
  scanf("%c",&p->sex);
  getchar();
  printf("請輸入年齡:");
  scanf("%d",&p->age);
  system("cls");print();
  if(n==1)
   head=p;
  else
   q->next=p;
  q=p;
  n++;
 }
  q->next=NULL;
  display(head);
  return head;
}
 void found(struct student *head)
{
 struct student *p;int n;
 printf("請輸入學號：");
 scanf("%d",&n);system("cls");print();
 p=head;
 if(head==NULL)
           {printf("沒有找到,/n這是一個空鏈表！/n"); }  
 else
    {while(p->num!=n&&p->next!=NULL)
 {
  p=p->next;
 }
 if(p->num==n)
              printf("%-4ld        %-8s          %-1c         %-2d/n",p->num,p->name,p->sex,p->age);
    else
         printf("沒有找到！");
 
}
       
}
struct student *del(struct student *head)
{
 struct student *p,*q;int n;
 printf("輸入學生的學號：");
 scanf("%d",&n);system("cls");print();
 if(head==NULL)
  {printf("這是一個空鏈表！");return head;}
 p=head;
 while(p->num!=n&&p->next!=NULL)
 {
  q=p;
  p=p->next;
 }
 if(p->num==n)
  {
   if(head==p)
    head=p->next;
   else
    q->next=p->next;
   free(p);
  }
 else
  printf("沒有找到！/n");

 return head;

}
struct student *input(void)
{struct student *p;
        p=(struct student *)malloc(sizeof(struct student ));
  printf("/n請輸入學號：");
  scanf("%ld",&p->num);
  getchar();
  printf("請輸入姓名：");
  scanf("%s",p->name);
  getchar();
  printf("請輸入性別：");
  scanf("%c",&p->sex);
  getchar();
  printf("請輸入年齡:");
  scanf("%d",&p->age);
  system("cls");print();
  return p;

}
struct student *insert(struct student *head,struct student *r)
{
 struct student *p,*q; 
  p=head;
  if(head==NULL)
  {
   head=r;
   r->next=NULL;
  }
  else
            {while(p->num>r->num&&p->next!=NULL)
      {
    q=p;
    p=p->next;
      }
      if(p->num<=r->num)
      {
                 if(head==p)
               head=r;
               
       else
             q->next=r;
                 r->next=p;

            }
    else
     {
   p->next=r;
   r->next=NULL;
     }
 }
   return head;
}
void print(void)
{
    printf("學生管理系統:/n");
 printf("1、創建列表/n");
 printf("2、查找/n");
 printf("3、增加/n");
 printf("4、刪除/n");
 printf("5、顯示/n");
 printf("6、退出系統/n/n/n/n");
}
int  main(void)
{
 struct student *r,*head=NULL;
 int m;int i;
  print();
 for(i=0;;i++)
 {
  scanf("%d",&m);system("cls");print();
  switch(m)
  {
   case 1:  head=creat();break;
   case 2:  found(head);break;
   case 3:  {r=input();head=insert(head,r);}break;
   case 4:         head=del(head);break;
   case 5:         display(head);break;
   case 6:         exit(0);
   default:   printf("輸入錯誤，請再次輸入！");
 } }
return 0;
}