prefix and postfix operators c++ - 


class compl{     float re,im;  public:     compl(float r, float i)         {re=r; im=i;}     compl& operator++()         {++re; return*this;} //(1)     compl operator++(int k){         compl z=*this; re++; im+=k; return z;} //(2)     friend compl& operator--(compl& z)         {--z.re; return z;}     friend compl operator--(compl& z,int k)         {compl x=z; z.re--; z.im-=k; return x;} };

(1) why have return current object reference? understood, reference second name something.

(2) why have save current object in z, change object , return unchanged z? doing this, returning value not increased. because of way postfix operator works(it returns old value, , increases it)

(1) don't have to, it's idiomatic because allows chaining operators or calls.

(2) yes, postfix should return previous value.


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