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Yeah, I know that's what I need to do now but I don't know where to start. I have read through these forums on the subject as well. Thanks for the links though. Is it possible if someone could give me an example within my code and maybe I can go from there?
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I have added Parametrised and Copy constructors and operators += and +:
 123456789101112131415161718192021222324 class Complex { public: Complex& operator+=(const Complex& rhs) { this->r += rhs.r; this->i += rhs.r; return *this; } Complex(int r_, int i_) : r(r_), i(i_) {} Complex(const Complex& rhs) : r(rhs.r), i(rhs.i) {} private: int r; int i; }; Complex operator+(const Complex& lhs, const Complex& rhs) { Complex temp(lhs); temp += rhs; return temp; }
EDIT: no need for operator+ to be friend or member.
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Thank you very much. So, when you supplied those constructors and operators, now would my next step would be to formulate a code on how to add/subtract/multiply/as well as - (unary) the complex numbers?
Yes, it is like that. You migt want to provide default constrctor (creating 0, 0 number). Also provide operators @ and @= in pairs, so people will not be suprised by some unexpected behavior.
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Multiplication is slightly harder than that. Google it or look it up at wikipedia.

Unary minus should reverse signs of both real and imaginary part of copy of *this and return said copy

Example of << operator:

 12345678 //in class body: friend std::ostream& operator<<(std::ostream&, const Complex&) //outside: std::ostream& operator<<(std::ostream& lhs, const Complex& rhs) { return lhs << '(' << rhs.r << " + " << rhs.i << "i)"; }
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1) operator== should return bool, so sigature would be
bool operator==(const Complex&, const Complex&)

2) It just calling itself now. Think, how do you decide that two complex numbers are equal and implement it in code (Hint: you will need access to cimplex internal, so you should declare it friend, as with operator<<)
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You need to watch your cut and pasting, I think. You have a repeated mistake, e.g.

 123456 Complex& operator+=(const Complex& rhs) { this->r += rhs.r; this->i += rhs.r; // <= ??? return *this; }

Shouldn't this/lhs and rhs be working with r and i consistently??

Andy
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Yes - for addition and subtraction, and the comparison operators

But not multiplication (as MiiNiPaa has already mentioned) or division, which are more involved.

Andy

Complex Multiplication
http://mathworld.wolfram.com/ComplexMultiplication.html

Complex Division
http://mathworld.wolfram.com/ComplexDivision.html

Also, you don't need both a member function and a global comparison operator. Just use the member function.

And whatever is at line 37 is not a comparison operator (it shouldn't take a std::ostream&, it should return a bool value which is the result of the comparison, ...)

Andy
Thanks for your advice, its just I'm getting more confused the more I think about it. Do you think you can tell me what lines like I need to delete and which are my member functions?

I'm guessing the +,-,etc. are my member functions and the += and -=, etc. are the global comparison operators.

Again, I haven't taken a class yet, I'm teaching myself at the moment, sorry if I sound like I don't know anything at all. It's just I've been at this example for hours . At this point, I wish I could just look at the solution code to teach myself, but the book doesn't provide solutions for even numbers and the more I read into these new codes and variables and what not, the more confused I am...
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Your multiplication is wrong. It's basically the foil process in mathematics, just with complex numbers and i.
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1) lines 48- 50 have no effect: there is return before them. You should remove excess code.
2) You cannot have friend definition inside class, only declaration. Move operator << definition outside class as you did there http://www.cplusplus.com/forum/general/112890/#msg617097 .
3) To give operator access to class internals you can use friend declaration. Look how it was done in case of operator<< and add similar declaration adapted to your class.
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