c++구조체와 함수를사용해서 성적표만들기2

#include <iostream>
using namespace std;
struct student{
 
 int no;
 char name[30];
 int kor;
 int eng;
 int math;
 int science;
 int total;
 double avg;
 int rank;
};

void getTotAvg(student *pclass, int Size)
{
 for(int i=0; i<Size; i++)
 {
 pclass->total = 0;
 pclass->total = pclass->kor + pclass->eng + pclass->math+ pclass->science
 pclass->avg = pclass->total / 4.0;

  

void calc_rank(student *pclass, int Size )
{
 for(int i=0; i<Size; i++)
 {
  pclass->rank = 1;
  for(int j=0; j<Size; j++)
  {
   if(i == j) continue;
   if(pclass->total < pclass->total)
   pclass->rank++;
  }
 }
}
void standingTest(student *pclass, int Size)
{

 Test temp;
 for(int i=0; i<Size; i++)
 {
  for(int j=i+1; j<Size; j++)
  {
   
   if(pclass->rank > pclass->rank)
   { 
    temp = pclass;
    pclass = pclass;
    pclass = temp;
   }
  }
 }

}
int input_class(student *pclass)
{
 char yesno;
 int count;
 do{
  cout<<"학번:";
  cin>>pclass->no;
  cout<<"성명:";
  cin>>pclass->name;
  cout<<"국어점수:";
  cin>>pclass->kor;
  cout<<"영어점수:";
  cin>>pclass->eng;
  cout<<"수학점수:";
  cin>>pclass->math;
  cout<<"과학점수:";
  cin>>pclass->science;
  cout<<"계속 입력하시겠습니까?[y/n]";
  cin>>yesno;
  count++;
  if(yesno=='y'||yesno=='Y') pclass++;
 }while(yesno=='y'||yesno=='y');
 return count;
}

void output_class(student *pclass,int Size)
{
 int count;
 cout<<"===================================================="<<endl;
 cout<<"학번  성명  국어  영어  수학  과학  총점  평균  석차"<<endl;
 for(int i=0; i<Size; i++)
 {
     cout.precision(2);
  cout << fixed;

  cout << setw(5) <<pclass->rank << setw(5) << pclass->No
                           << setw(5) << pclass->Kor  << setw(5) << pclass->eng
                           << setw(5) << pclass->math << setw(5) <<pclass->science
                           << setw(7) << pclass->total <<pclass->avg "\n";
 }
}

void screen()
{
 student class_a[35];
 student *pclass;
 pclass=class_a;

 int select_menu=0,status=0,count=0;
 char yes_no;

  cout<<"============================="<<endl;
  cout<<"     1. 데이터 입력"<<endl;
  cout<<"     2. 데이터 출력"<<endl;
  cout<<"     3. 종료       "<<endl;
  cout<<"============================="<<endl;
  cout<<" 원하는 메뉴를 고르시오  : ";
  cin>>select_menu;
  cout<<" 프로그램을 종료하시겠습니까?[y/n]";
  cin>>yes_no;
  if(yes_no=='y'||yes_no=='Y') status=1;
}

void main()
{
 screen();
}

이거 먼가이상합니다
작동제대로하게좀
손봐주세요 ㅠ.ㅠ
구조체와 함수사용인데
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