C++ Program : To Swap two number

#include<iostream.h>
#include<conio.h>

class num
{
   int a;
    public:
   void swap(int&x,int&y)
   {
      a=y;
      y=x;
      x=a;
   }
};

int main()
{
   clrscr();
   int a,b;
   cout<<"Enter the number a and b :";
   cin>>a>>b;
   cout<<"\na="<<a<<"\nb="<<b;
   num n;
   n.swap(a,b);
   cout<<"\na and b swaped \na="<<a<<"\nb="<<b;
   getch();
   return 0;

}

Class diagram 

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