C - C++ Friend Class

#include <iostream>
using namespace std;
 
class TwoValues
{
  int a;
  int b;
 
public:
  TwoValues(int i, int j) { a = i; b = j; }
  friend class Min;
};
 
 
class Min 
{
public:
  int min(TwoValues x);
};
 
 
int Min::min(TwoValues x)
{
  return x.a < x.b ? x.a : x.b;
}
 
 
int main()
{
  TwoValues ob(10, 20);
  Min m;
 
  cout << m.min(ob);
 
  return 0;
}