Question

3. Using a programming language of your choice, write a complete and fully functional program that uses reference and pointer types to swap two double precision floating-point numbers. The two numbers are read in by the program’s user. Use a proper prompt for each number.
   1. Use one function that uses formal parameter reference types to swap the two numbers
   2. Use another function that uses formal parameter pointer types to swap the two numbers.
   3. In the main or driver function, call these two functions with the actual arguments received from the program’s user
   4. Display immediately the result of the swapping after each function call in the calling function (the main function or the driver) before the next function call to see whether the numbers are swappe Use a proper display message.

Answer 1

C++ CODE:

#include<iostream>
#include<iomanip>

using namespace std;

// function to swap variables using reference
void swap_ref(int& n1, int& n2)
{
    int temp;
    temp = n1;
    n1 = n2;
    n2 = temp;
}

//function to swap variables using pointers
void swap_ptr(double *p,double *q)
{
   double temp;
   temp=*p;
   *p = *q;
   *q=temp;
}

int main()
{
   //variable to store the input values
   double x,y;
  
   //temporary variables
   double t1,t2;
  
   // user input from the user
   cout<<"Enter a floating point number: ";
   cin>> x;
  
   cout<<"\nEnter another floating point number: ";
   cin>>y;
  
   //copying the input values to temporary variables
   t1=x;
   t2=y;
  
   cout<<"\n\nSwapping the variables using reference\n";
  
   // the value of x and y before swapping
   cout<<"\n\nBefore Swapping\n"<<endl;
   cout<<"The value of x is : "<<setprecision(2)<<fixed<<x<<endl;
   cout<<"The value of y is : "<<setprecision(2)<<fixed<<y;
  
   //calling the function
   swap(x,y);
  
   //the value of x,y after swapping
   cout<<"\n\nAfter Swapping\n"<<endl;
   cout<<"The value of x is : "<<setprecision(2)<<fixed<<x<<endl;
   cout<<"The value of y is : "<<setprecision(2)<<fixed<<y;
  
   // reinitialize the value of x and y to user input values
   x=t1;
   y=t2;
  
   cout<<"\n\nSwapping the variables using pointers\n";
   // the value of x and y before swapping
   cout<<"\nBefore Swapping\n"<<endl;
   cout<<"The value of x is : "<<setprecision(2)<<fixed<<x<<endl;
   cout<<"The value of y is : "<<setprecision(2)<<fixed<<y;
  
   //calling the function
   swap_ptr(&x,&y);
  
   //the value of x,y after swapping
   cout<<"\n\nAfter Swapping\n"<<endl;
   cout<<"The value of x is : "<<setprecision(2)<<fixed<<x<<endl;
   cout<<"The value of y is : "<<setprecision(2)<<fixed<<y;
  
   return 0;
}

SCREENSHOT FOR OUTPUT: