C++ Programs to SWAP BY FUNCTIONs, through call by VALUE ,ADDRESS & REFERENCE

/*swap function by address,value and reference in c++, in each case the program require an user input*/


#include<iostream.h>
#include<stdlib.h>   //For system("pause")
//using namespace std; uncomment if using MS Visual Studio

void swapv(int , int );    //For Swapping by value

void swapa(int *,int *); //For Swapping by address

void swapr(int &,int &); //For Swapping by reference

void main(void)
{
 int a1,b1;
 cout<<"Enter value of a1 and b1 for swapping by value:   ";
 cin>>a1>>b1;
 swapv(a1,b1);   //call by value.
 cout<<"swap is ="<<"a1:  "<<a1<<"\t"<<"b1:  "<<b1<<endl;

 int a2,b2;
 cout<<"Enter value of a2 and b2 for swapping by address:   ";
 cin>>a2>>b2;
 swapa(&a2,&b2);    //call by address.
 cout<<"swap is "<<"a2:   "<<a2<<"\t" <<"b2:   "<<b2<<endl;

 int a3,b3;
 cout<<"Enter the value of a3 and b3 for swapping by refrence:  " ;
 cin>>a3>>b3;
 swapr(a3,b3);     //call by reference.
 cout<<"swap is " <<"a3:   "<<a3<<"\t"<<"b3:   "<< b3<<endl;

 system("pause");
}

void swapv(int x,int y)
{
 int t=x;
     x=y;
     y=t;
}

void swapa(int *x,int *y)
{
 int t=*x;
     *x=*y;
     *y=t;
}

void swapr(int &x,int &y)
{
 int t=x;
     x=y;
     y=t;
}  //End of the code

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