why friend function not working in C++?

Question

// compiler show error.
// https://www.sololearn.com/compiler-playground/cno6jtPGQqyW

#include <iostream>

using namespace std;

class B;
class A
{
private:
void printName()
{
cout << "xyz\n";
}

void printWeight()
{
cout << "40kg\n";
}

friend void B::showInfo(A);
};

class B
{
public:
void showInfo(A obj)
{
obj.printName();
obj.printWeight();
}
};

int main()
{
A objA;
B objB;

objB.showInfo(objA);
return 0;
}

Answer 1

Rishi ,
Lots of mistake in your code..

#Missing class A declaration..

#For fix the error, need to reorder the class declarations so that class B is declared before class A.

See this modified code..
https://code.sololearn.com/cwt53IJ16zQ9/?ref=app

Answer 2

Rishi Try again..

Answer 3

Worked!

Answer 4

Aziz