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

typedef struct student{
 int no;
 char name[20];
 char major[20];
 struct student *link;
}student;  

typedef struct
{
 student* head; 
}LList_h;  

add();
printList();

main(void)
{
 int choice;
 int no;
 char name[20],major[20];

 LList_h* head;    
 head = (LList_h*)malloc(sizeof(LList_h));
 head -> head = NULL;

 while(1)
 {
  printf("\\n\\t============================================================\\n"); 
  printf("\\t1. 입력 2. 학번순으로 정렬되어 출력 3. 학번으로 검색 4. 종료\\n");
  printf("\\t============================================================\\n");
  scanf("%d",&choice);
   
  switch(choice)
  {
  case 1:
   printf("학번, 이름, 학과를 입력하세요\\n");
   scanf("%d %s %s", &no, name, major);
   add(head, no, name, major);
   break;
  case 2:
   printList(head);
   break;
  case 3:
   printf("3번을 선택했슈");
   break;
  case 4:
   exit(1);
   break;
  }
 }
}

add(LList_h* head, int no, char name[20], char major[20])
{
 student *newStudent;
 student *p;
 newStudent = (student*)malloc(sizeof(student));
 

 p = head -> head;

 newStudent -> no = no;
 strcpy(newStudent->name,name);
 strcpy(newStudent->major,major);
 newStudent -> link = NULL;

 newStudent -> link = p -> link;
 p -> link = newStudent;
}

printList(LList_h* head)
{
 student *p;

 p = head -> head;

 while(p -> link != NULL)
 {
  printf("%s -> ", p -> name);
  p = p -> link;
 }
 
}

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