opovrld bin r.i.p

#include<iostream.h>

class complex
{
    float r,i;
public:
    complex()
    {
        r=0;
        i=0;
    }

    complex(float a,float b)
    {
        r=a;
        i=b;
    }

    complex operator+(complex k)
    {
        complex t;
        t.r=r+k.r;
        t.i=i+k.i;
        return t;
    }

    complex operator-(complex k)
    {
        complex t;
        t.r=r-k.r;
        t.i=i-k.i;
        return t;
    }

    complex operator*(complex k)
    {
        complex t;
        t.r=(r*k.r-i*k.i);
        t.i=(r*k.i+i*k.r);
        return t;
    }

    complex operator/(complex k)
    {
        complex t;
        t.r=(r*k.r-i*k.i)/(k.i*k.i+k.r*k.r);
        t.i=(-r*k.i+i*k.r)/(k.r*k.r+k.i*k.i);
        return t;
    }

    void display()
    {
        cout<<"\n\nresult is "<<r<<" +j "<<i<<" \n";
    }
};

int main()
{
    float l[3],w[3];
    int a,t=1,i;
    complex p,q,s;
    do
    {
        cout<<"\n\nenter the values of two complex nos\n";
        for(i=0;i<2;i++)
        {
            cout<<"real part of "<<i+1<<" complex No.\n";
            cin>>l[i];
            cout<<"imaginary part of "<<i+1<<" complex No.\n";
            cin>>w[i];
        }
        p=complex(l[0],w[0]);
        q=complex(l[1],w[1]);
        cout<<"\n\nenter a choice:\n";
        cout<<"1.addition of complex nos\n";
        cout<<"2.subtraction of complex nos\n";
        cout<<"3.multiplication of complex nos\n";
        cout<<"4.division of complex nos\n";
        cout<<"5.exit\n";
        cin>>a;
        switch(a)
        {
        case 1:
            s=p+q;
            s.display();
            break;

        case 2:
            s=p-q;
            s.display();
            break;

        case 3:
            s=p*q;
            s.display();
            break;

        case 4:
            s=p/q;
            s.display();
            break;

        case 5:
            t=0;
            break;

        default:
            cout<<"invalid\n";
            break;
        }
    }while(t!=0);
    return 0;
}