Question

1.Write a c++ program to find Maximum out of two numbers using friend function. Here one member is of one class and second belongs to another class.

2.Write a c++ program to swap the values of private data members of classes names classOne and classTwo using friend keyword.

Answer 1

program for problem 1

#include <iostream>
#include<conio.h>
#include<stdio.h>
using namespace std;
// declaring type
class two;
class one
{
        int x;
        public:
                // using friend function
        friend void max(one,two);
        }first;
class two
{
        int y;
        public:
        friend void max(one,two);
        }second;
        
void max(one x,two y)
{
        // declaring number1 and number2
        int number1,number2;
        // prompting user 
        cout << "Enter a positive integer: ";
        // taking input
    cin >> number1;
    // assigning number1 to class one member x
        x.x=number1;
        cout << "Enter a positive integer: ";
    cin >> number2;
    // assigning number1 to class two member y
        y.y=number2;
        cout<<"\nFirst no: "<<x.x;
        cout<<"\nSecond no: "<<y.y;
        // comparing numbers
        if(x.x>y.y)
        {
        cout<<"\n"<<x.x<<" is maximum";
        }
        else
        {
        cout<<"\n"<<y.y<<" is maximum";
        }
}
int main()
{
        // calling 
        max(first,second);
        getch();
}

OUTPUT SCREEN

program 2 solution

#include <iostream>
using namespace std;

// declaring class one
class one;
// declaring class two
class two
{
public:
  void print(one& x);
};

class one
{
  int a, b;
  friend void two::print(one& x);
public:
  one() : a(1), b(2) { }
};

void two::print(one& x)
{
        // printing output
        cout << "a is " << x.a << endl;
        cout << "b is " << x.b << endl;
}

int main()
{
        
        // creating objects to one and two classes
        one Oneobj;
        two Twoobj;

        Twoobj.print(Oneobj);
}