#include <iostream>
#include <cassert>
#include <fstream>
#include <iomanip>
#include <math.h>

using namespace std;

class Complex {
    private:
    double real;
    double imaginary;
    public:
    Complex();
    Complex(double r, double i);
    Complex* add(Complex* c2);
    Complex* sub(Complex* c2);
    Complex* sub2(Complex & c2);
    Complex* mul(Complex* c2);
    void print();
};
Complex::Complex() {
    real=0.0;
    imaginary=0.0;
}
Complex::Complex(double r, double i) {
    real=r;
    imaginary=i;
}
Complex* Complex::add(Complex* c2) {
    assert(c2!=NULL);
    Complex* result=new Complex(real+c2->real,imaginary+c2->imaginary);
    // Point 1
    return result;
}
Complex* Complex::sub(Complex* c2) {
    assert(c2!=NULL);
    Complex* result=new Complex(real-c2->real,imaginary-c2->imaginary);
    return result;
}
Complex* Complex::sub2(Complex & c2) {
    Complex* result=new Complex(real-c2.real,imaginary-c2.imaginary);
    // Point 2
    return result;
}
Complex* Complex::mul(Complex* c2) {
    assert(c2!=NULL);
    Complex* result=new Complex(
	    real*c2->real - imaginary*c2->imaginary,
	    real*c2->imaginary + imaginary*c2->real);
    return result;
}
void Complex::print() {
    cout << real<<" + "<<imaginary<<"i"<<endl;
}

#define ADD 0
#define SUB 1
#define MUL 2
Complex* process(Complex* c1, Complex* c2, int op);

Complex* process(Complex* c1, Complex* c2, int op) {
    assert(c1!=NULL);
    assert(c2!=NULL);
    if (op==ADD) {
	return c1->add(c2);
    }
    else if (op==SUB) {
	return c1->sub(c2);
    }
    else {
	assert(op==MUL);
	return c1->mul(c2);
    }
}

Complex* process2(Complex* c1, Complex* c2, int op) {
    assert(c1!=NULL);
    assert(c2!=NULL);
    assert(op>=ADD && op<=MUL);
    static Complex* (Complex::*a[3])(Complex*)={
	&Complex::add,&Complex::sub,&Complex::mul};
    Complex* (Complex::*op_func)(Complex*)=a[op];
    return (c1->*op_func)(c2);
}

double bad_multiply(int i1, int i2) {
    return (double)(i1*i2);
}

int main() {

    Complex a(1.0,2.0);
    Complex &ref=a;
    Complex* p0=new Complex(0.0,0.1);
    // Point 0
    Complex b(2.0,3.0);
    Complex c(5.0,4.0);
    Complex d(3.0,8.0);
    Complex* p1=a.add(&b);
    Complex* p2=c.sub2(d);
    Complex* p3=d.sub(&a);
    Complex* p4=process(&a,&b,MUL);
    Complex* p5=process2(&a,&b,MUL);
    Complex e(*p4);

    p1->print();
    p2->print();
    p3->print();
    p4->print();
    p5->print();
    e.print();

    delete p1;
    p1=NULL;
    delete p2;
    p2=NULL;
    return 0;
}