swap.cpp

---

//Program to demonstrate call-by-reference parameters.

#include <iostream>

using namespace std;

void getNumbers(int& input1, int& input2);
//Reads two integers from the keyboard.

void swapValuesValue(int variable1, int variable2);
//Interchanges the values of variable1 and variable2.
//Call-by-value

void swapValuesReference(int& variable1, int& variable2);
//Interchanges the values of variable1 and variable2.
//Call-by-reference

void showResults(int output1, int output2);
//Shows the values of variable1 and variable2, in that order.

int main( )
{
    int firstNum, secondNum;

    getNumbers(firstNum, secondNum);
    swapValuesValue(firstNum, secondNum);
    showResults(firstNum, secondNum);

    swapValuesReference(firstNum, secondNum);
    showResults(firstNum, secondNum);
    cout << endl;

    return 0;
}

void getNumbers(int& input1, int& input2)
{
    cout << "\nEnter two integers: ";
    cin >> input1
        >> input2;
}

void swapValuesValue(int variable1, int variable2)
{
    int temp;
    cout << "\nEntering Swap by Value:\n";
 
   temp = variable1;
    variable1 = variable2;
    variable2 = temp;
}

void swapValuesReference(int& variable1, int& variable2)
{
    int temp;
    cout << "\nEntering Swap by Reference:\n";

    temp = variable1;
    variable1 = variable2;
    variable2 = temp;
}

void showResults(int output1, int output2)
{
    cout << "In reverse order the numbers are: "
         << output1 << " " << output2 << endl;
}