armstrong c++

/*program to check if a number is a armstrong number or not*/
#include <iostream>

using namespace std;
class armstrong
{
    private:
        int number,num[6],sum,upper,lower;
    public:
        void getdata()
        {
            cout<<"\nENTER THE NUMBER : ";
            cin>>number;
            sum=0;
            upper=0;
            lower=0;
            num[0]=0;num[1]=0;num[2]=0;num[3]=0;num[4]=0;num[5]=0;
        }
        void check()
        {
            int temp=0,n=0,i=0;
            n=number;
            while(n!=0)
            {
                temp=n%10;
                n=n/10;
                num[i]=temp;
                i++;
            }
            i--;
            while(i>=0)
            {
                sum=sum+num[i]*num[i]*num[i];
                i--;
            }
            if(sum==number)
            {
                cout<<"\nTHE ENTERED NUMBER IS AN ARMSTRONG NUMBER";
            }
            else
            {
                cout<<"\nTHE ENTERED NUMBER IS NOT AN ARMSTRONG NUMBER";
            }
        }

        void getrange()
        {
            cout<<"\nENTER THE UPPER LIMIT : ";
            cin>>upper;
            cout<<"\nENTER THE LOWER LIMIT : ";
            cin>>lower;
            sum=0;
            num[0]=0;num[1]=0;num[2]=0;num[3]=0;num[4]=0;num[5]=0;
        }
        void checkrange()
        {

            int temp=0,n=0,i=0,j=lower;
            cout<<"\nTHE ARMSTRONG NUMBERS IN THE GIVEN RANGE ARE :";
            while(j<=upper)
            {
                n=j;
                i=0;
                while(n!=0)
                {
                    temp=n%10;
                    n=n/10;
                    num[i]=temp;
                    i++;
                }
                while(i>=0)
                {
                    sum=sum+num[i]*num[i]*num[i];
                    i--;
                }
                if(sum==j)
                {
                    cout<<"\n"<<j;
                }
                j++;
                sum=0;
            }
        }
};
int main()
{
    armstrong a1;
    int choice=0,cont=0;
    do
    {   wrong :
            cout<<"\n\nPROGRAM TO CHECK FOR ARMSTRONG NUMBER "<<endl;
            cout<<"THE FOLLOWING CHOICES ARE AVAILIABLE "<<endl;
            cout<<"1.CHECK ENTERED NUMBER "<<endl;
            cout<<"2.PRINT ALL ARMSTRONG NUMBERS IN A GIVEN RANGE "<<endl;
            cout<<"ENTER YOUR CHOICE : ";
        cin>>choice;
        if(choice!=1 && choice !=2)
        {
            cout<<"YOU'VE ENTERED WRONG CHOICE :"<<endl;
            goto wrong;
        }
        else
        {
            switch(choice)
            {
            case 1:
                a1.getdata();
                a1.check();
                break;

            case 2:
                a1.getrange();
                a1.checkrange();
                break;
            }
        }
        cout<<"\nDO YOU WANT TO CHECK AGAIN (1/0):";
        cin>>cont;
    }while(cont==1);
    return 0;
}