chi square

#include<iostream>


using namespace std;

class chisquare
{
    private:
        int n, observed[20],i,N,Expected;
        float Calculation[20],final,critical;

    public:
        chisquare() //constructor to initialize values
        {
            N=0;
            final=0.00;
        }

        void getdata() //getting observed frequency
        {
            cout<<"How many numbers:?"<<endl;
            cin>>n;
            cout<<"Enter the observed frequency:"<<endl;
            for(i=0;i<n;i++)
            {
                cout<<"Enter "<<i+1<<"th number: "<<endl;
                cin>>observed[i];
            }
        }


        void calculation() //calculation of N(total frequency), Calculation(((Oi-Ei)^2/Ei)),final(?)
        {
            for(i=0;i<n;i++)
            {
                N=N+observed[i];
            }
            Expected=N/n;
            for(i=0;i<n;i++)
            {
                Calculation[i]=(float)((observed[i]-Expected)*(observed[i]-Expected))/Expected;
                final=final+Calculation[i];
            }
        }

        void display() //display in tabulated format
        {
            cout<<"S.No"<<"\t";
            cout<<"Oi"<<"\t";
            cout<<"Ei"<<"\t";
            cout<<"((Oi-Ei)*(Oi-Ei))/Ei"<<endl;
            for(i=0;i<n;i++)
            {
                cout<<i+1<<"\t";
                cout<<observed[i]<<"\t";
                cout<<Expected<<"\t";
                cout<<Calculation[i]<<endl;
            }
            cout<<"-------------------------------------------------------"<<endl;
            cout<<"Total sum of Oi:"<<N;
            cout<<"calculation is: "<<final;
            cout<<endl;
        }


        void conclusion() //compare tabulated and calculated value and conclude if Ho is accepted.
        {
            cout<<endl;
            cout<<"Enter the critical value:"<<endl;
            cin>>critical;
            if(final<critical)
            {
                cout<<"The test is accepted"<<endl;
            }
            else
            {
                cout<<"The test is rejected"<<endl;
            }
        }

};
int main()
{
    chisquare c;
    c.getdata();
    c.calculation();
    c.display();
    c.conclusion();

    return(0);
}