Question

c++

Note:
Do not use using namespace std;

Use std::

Use comments for clear understanding

TEST THE PROGRAM.

1) Create a c++ program to run a simple experiment to see how reference parameters work.
2) You need to add a “&” symbol after the parameter type specification to set up a reference parameter:
int myfunc (int & x) {
x = 11;
return -11;
}

int testdata = 0;
int y;

y= myfunc (testdata);
3) Now, You can get a normal return value from our function. But a hidden side effect is possible as well. If myfunc modifies the parameter variable (x in this case), the caller’s testdata will be modified. It is important.

Things to do:
You are to build a project that has three files:
• main.cpp
• compare.cpp
• compare.h
The Compare Function
The “compare.cpp” file contains one function, also named “compare”. This function takes two integer reference parameters with names “param1” and “param2” and compares them. It returns a single character based on what it sees. Here is what you are to return:
• “=” if the two values are equal
• “<” if param1 is less than param2
• “>” if param1 is greater than param2
Just to prove that the “compare” function really does have access to your caller’s variables, have the function flip the sign of each parameter before you process the return statement you need in this function:
param1 = -param1;
param2 = -param2;
WarningThis will mess up your final output, but that is fine for what we are trying to see here!)
The Main Function
Set up the main program that asks the user for two integer numbers, which are stored in variables named “var1” and “var2”. The main program then calls the “compare” function described above, passing in the parameters “var1” and “var2”. Once you have the return character, you are to test that character and print out a more complete English statement about the result. For example, if you get back an “equal sign” character, you will print out this:
• 1234 is equal to 1234

Since you flipped the sign in the compare function, you will actually see negative values here, not the positive values the user entered).
Add output statement similar to the above for the other two possible return characters.

Answer 1

compare.h :

//header file for compare function file

#ifndef COMPARE_H
#define COMPARE_H
char compare(int &param1, int &param2);
#endif

compare.cpp :

#include "compare.h" //include the header file compare.h

char compare(int &param1,int &param2){ //definition of function using reference variable
    param1=-param1; //change the sign of variable param1
    param2=-param2; //change the sign of variable param1
  
    //return = or > or < depending on whether the variable are equal,1st is greater or the 1st id smaller
    if(param1==param2)
        return '=';
    else if (param1<param2)
        return'<';
    else
        return '>';
}

main.cpp :

#include <iostream>
#include "compare.h" //inclue the file

int main()
{
    int var1,var2;
    char sign;
    //take var1 value from user
    std::cout<<"Enter the first integer value: ";
    std::cin>>var1;
  
    //take var2 value from user
    std::cout<<"Enter the second integer value: ";
    std::cin>>var2;
  
    //call the compare function and store the returned value in sign variable
    sign=compare(var1,var2);
  
    //print statement depending on the sign value
    //The sign of variable var1 and var2 will be changed from the one entered by the user as they were modified in the compare function
    if(sign=='=')
        std::cout<<var1<<" is equal to "<<var2;
    else if(sign=='>')
        std::cout<<var1<<" is greater than "<<var2;
    else
        std::cout<<var1<<" is less than "<<var2;
    return 0;
}

Output:

Enter the first integer value: 34 er the second integer value: 12 34 is less than -12

You will observe that the sign of variable var1 and var2 are changed after they are paased to compare function as reference.