Program:

    #include<iostream.h>
    #include<conio.h>
    #inclde<iomanip.h>

    class complex
    {
    float real,imag;
    public:
    complex()
    {
    real=0;
    imag=0;
    }
    void read();
    void write();
    friend complex operator+(complex c1,complex c2);
    friend complex operator-(complex c1,complex c2);
    friend complex operator*(complex c1,complex c2);
    friend complex operator/(complex c1,complex c2);
    };
    void complex::read()
    {
    cout<<setw(10)<<"\tEnter the real part: ";
    cin>>real;
    cout<<setw(10)<<"\n\tEnter the imaginary part: ";
    cin>>imag;
    }
    void complex::write()
    {
    if(imag>1)
    cout<<setw(10)<<real<<"+"<<imag<<"i"<<endl;
    else
    cout<<setw(10)<<real<<" "<<imag<<"i"<<endl;
    }
    complex operator+(complex c1,complex c2)
    {
    complex t;
    t.real=c1.real+c2.real;
    t.imag=c1.imag+c2.imag;
    return(t);
    }
    complex operator-(complex c1,complex c2)
    {
    complex t;
    t.real=c1.real-c2.real;
    t.imag=c1.imag-c2.imag;
    return(t);
    }
    complex operator*(complex c1,complex c2)
    {
    complex t;
    t.real=(c2.real*c1.real)-(c2.imag*c1.imag);
    t.imag=(c2.imag*c1.real)-(c2.real*c1.imag);
    return(t);
    }
    complex operator/(complex c1,complex c2)
    {
    complex t;
    t.real=(c1.real*c2.real+c1.imag*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag);
    t.imag=(c1.imag*c2.real-c1.real*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag);
    return(t);
    }
    void main()
    {
    complex c1,c2,c3,c4,c5,c6;
    char c="Y";
    clrscr();
    do{
    cout<<" "<<setw(10)<<"\n\nEnter the first complex number \n\n\n";
    c1.read();
    cout<<" "<<setw(10)<<"\n\nEnter the second complex number \n\n\n";
    c2.read();
    c3=c1+c2;
    c4=c1-c2;
    c5=c1*c2;
    c6=c1/c2;
    clrscr();
    cout<<"\nINPUT : \n\n";
    cout<<"\n\n\tFIRST COMPLEX NUMBER : ";
    c1.write();
    cout<<"\n\n\tSECOND COMPLEX NUMBER : ";
    c2.write();
    cout<<"\nOUTPUT : \n\n";
    cout<<"\n\tCOMPLEX ADDITION : ";
    c3.write();
    cout<<"\n\tCOMPLEX SUBTRACTION : ";
    c4.write();
    cout<<"\n\tCOMPLEX MULTIPLICATION : ";
    c5.write();
    cout<<"\n\tCOMPLEX DIVISION : ";
    c6.write();
    cout<<setw(10)<<"\n\n DO YOU WANT TO CONTINUE ";
    c=getche();
    }
    while(c!='n'&&c!='N');
    getch();
    }