[C++]클래스를 이용한 기본 더하기

#include "iostream.h"
class counterclass
{
private : int value;
public : void adder(int n)
   {
    int i=0, add=0;
          while(i<=value){
       add += i;
         i++;
  }
 cout << add;
 cout << endl;}
   void setting(int i){value = i;}
};
void main()
{
 int n;
 cout << "\n input number:";
 cin >> n;
 counterclass counter01;
 counter01.setting(n);
 counter01.adder(n);
}