Anyone explain me something....

Question

I just created two programs of friend function see below,in c++ course they told that we have to pass object by reference.When i pass it by value its output is same?Explain.

"https://code.sololearn.com/coJxRfvk7HgY/?ref=app"

"https://code.sololearn.com/c21xPuhNAVA4/?ref=app"

Answer 1

pass by reference - giving you the power to change his values.
pass by value - creating totally new object, which you accessed him.

when you using 'friend' on some class it doesn't mean you always have to pass by reference to access his values.