Write a Program to find Maximum out of Two Numbers using friend function. Note: Here one number is a member of one class and the other number is member of some other class.

#include<iostream.h>
#include<conio.h>
class ABC;
class XYZ
{ 
int x;
public: 
void setvalue(int i) 
{ 
x=i; 
} 
friend void max(XYZ, ABC);
};
class ABC
{ 
int a;
public: 
void setvalue(int i) 
{ 
a=i; 
} 
friend void max(XYZ, ABC);
};
void max (XYZ m, ABC n)
{ 
if(m.x>=n.a) 
cout<<m.x; 
else 
cout<<n.a;
}
int main()
{ 
ABC abc; 
abc.setvalue(10); 
XYZ xyz; 
xyz.setvalue(20); 
max(xyz,abc);   
return 0;
}