C언어 ㄹㅈ

#include <iostream>
#include <string>
#include <fstream>
using namespace std;

const int MAX=3;

class Student
{
        string name;
        int score[2];
        int sum;
        double avg;
  int bmi;
  
public:
        string getName() { return name; } //이름
        int getScore(int i) { return score[i]; }
        int getSum() { return sum; } //표준체중
        int getAvg() { return avg; } //비만도
  int getBMI() { return bmi; } //비반정도
        void setName(string n) { name =n; }
        void setScore(int i, int s) { score[i] = s; }
        void calcSum() { sum = (score[0] -100)*0.9 ; } //표준체중 (키-100)*0.9
        void calcAvg() { avg = score[1]/sum*100; } //비만도 = 현재 체중/표준체중*100  void calcBMI() {
  void calcBMI() { bmi= avg;
   if(avg<85)
    cout<<"저체중";
   if((85<=avg)&&(avg<105))
    cout<<"정상";
   if((106<avg)&&(avg<115))
    cout<<"과제중";
   else
    cout<<"비만";
  }
  
};

int main()
{       
        Student std[MAX];
        ifstream input;       
        ofstream output;       
        int i;

        string name;
        int score1, score2;

        input.open("c:\student.txt");
        output.open("c:\student1.txt");

        if (input.fail() || output.fail())
                return 0;

        i = 0;
        while (!input.eof())
        {
            input >> name >> score1 >> score2;

            std[i].setName(name);
            std[i].setScore(0, score1);    std[i].setScore(1, score2);
           

            std[i].calcSum();    //표준체중
            std[i].calcAvg();  //비만도
   std[i].calcBMI();

            output << std[i].getName() << 't' << std[i].getScore(0) << 't'
                << std[i].getScore(1)
                << 't' << std[i].getSum() << 't' << std[i].getAvg() << 't'
    << std[i].getBMI()<<endl;

         i++;
            }

               input.close();
               output.close();
}