In what areas can I optimize this C++ program?

#include

#include

class complex

{

private:

float real,img;

public:

void assign(float x,float y)

{

real=x;

img=y;

}

void print()

{ if(img>=0)

cout<

else

cout<

getch();

}

};

void add( float a,float b,float c, float d)

{

float e,f;complex g;

e=a+c;

f=b+d;

g.assign(e,f);

g.print();

}

void sub( float a,float b,float c, float d)

{

float e,f;complex g;

e=a-c;

f=b-d;

g.assign(e,f);

g.print();

}

void mul( float a,float b,float c, float d)

{

float e,f; complex g;

e=a*c-b*d;

f=b*c+a*d;

g.assign(e,f);

g.print();

}

void main()

{

float a,b,c,d;

complex x,y,z;

clrscr();

cout<<" for complex 1:";

cout<<"real part:";

cin>>a;

cout<<"imaginary part:";

cin>>b;

cout<<" for complex 2:";

cout<<"real part:";

cin>>c;

cout<<"imaginary part:";

cin>>d;

x.assign(a,b);

y.assign(c,d);

cout<<"**************original data:************ ";

cout<<"Complex 1: ";x.print();

cout<<" Complex 2: ";y.print();

cout<<" ************=================********** ";

cout<<" Addition: ";add(a,b,c,d);

cout<<" Subtraction: ";sub(a,b,c,d);

cout<<" Multipication: ";mul(a,b,c,d);

}