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My homework has a bonus question.

Bonus question:

Declare two variables, one is of regular integer type and the other of unsigned integer type.
Find out their sizes.
Find out if those two variables are next to one another in the memory.
Find out the largest integer (signed or unsigned) that these two variables can hold.

I tried to use an if/else statement (at the bottom of the code) to determine this, but I get the error "comparison between distinct pointer types `int*' and `unsigned int*' lacks a cast" in these two lines:

Code:
if (&variableX+1 == &variableY){

Code:
if (&variableY+1 == &variableX){

Can anyone give me a hint on how I could resolve this problem?

Code:
//Assignment 1

#include <iostream>

using namespace std;

int main()

{

    //Declare a variable of double type

    double variableA;

    //Display the size of that variable

    cout << "The size of variableA: " << sizeof variableA << " bytes" << endl;

    //Display the location of that variable

    cout << "The address of the memory location of variableA: " << &variableA << endl;

    //Display what is in it before you put any data into it

    cout << "The contents of variableA: " << variableA << endl << endl;

    //Prompt the user to enter a number from the keyboard

    cout << "Enter a number: "; cin >> variableA;

    //then display the tripled value of the number

    cout << variableA << " multiplied by 3 is " << variableA*3 << endl << endl; 

    system("PAUSE");

    //Pick one other data type that C++ supports to do the same

    int variableB;

    //Display the size of that variable

    cout << "\nThe size of variableB: " << sizeof variableB << " bytes" << endl;

    //Display the location of that variable

    cout << "The address of the memory location of variableB: " << &variableB << endl;

    //Display what is in it before you put any data into it

    cout << "The contents of variableB: " << variableB << endl << endl;

    //Prompt the user to enter a number from the keyboard

    cout << "Enter a number: "; cin >> variableB;

    //then display the tripled value of the number

    cout << variableB << " multiplied by 3 is " << variableB*3 << endl << endl; 

    system("PAUSE");

//Bonus question:

    //Declare two variables, one is of regular integer type and the other of

    //unsigned integer type

    int variableX;

    unsigned variableY;

    //Find out their sizes

    cout << "\nNote: variableX is a signed int while variableY is an unsigned int";

    cout << "\n\nThe size of variableX is: " << sizeof variableX << " bytes";

    cout << "\nThe size of variableY is: " << sizeof variableY << " bytes" << endl;

    //Find out if those two variables are next to one another in the memory

    cout << "\nThe address of the memory location of variableX: " << &variableX << endl;

    cout << "The address of the memory location of variableY: " << &variableY << endl << endl;

    if (&variableX+1 == &variableY){

       cout << "They are next to one another in memory!" << endl;

       }

       else {

            if (&variableY+1 == &variableX){

               cout << "They are next to one another in memory!" << endl;

               }

               else {

                    cout << "They are not adjacent to one another in memory!" << endl;

                    }

               }

    system("PAUSE");

    return 0;

}

Nevermind.. I got it working with reinterpret_cast

What compiler do you use? Because MSVC gives a huge hint about this by saying "Types pointed to are unrelated; conversion requires reinterpret_cast".

This should work, even with the C style casting

Code:
#include <iostream>

using namespace std;

int main()

{

    unsigned variableY;

    int variableX;

    cout << "\nNote: variableX is a signed int while variableY is an unsigned int";

    cout << "\n\nThe size of variableX is: " << sizeof variableX << " bytes";

    cout << "\nThe size of variableY is: " << sizeof variableY << " bytes" << endl;

    cout << "\nThe address of the memory location of variableX: " << &variableX << endl;

    cout << "The address of the memory location of variableY: " << &variableY << endl << endl;

    if ((void*)&variableX < (void*)&variableY)

    {

        if (sizeof(int) == ((long)&variableY - (long)&variableX))

        {

            cout << "They are next to one another in memory!" << endl;

        }

        else

        {

            cout << "They are not adjacent to one another in memory!" << endl;

        }

    }

    else if ((void*)&variableX > (void*)&variableY)

    {

        if (sizeof(int) == ((long)&variableX - (long)&variableY))

        {

            cout << "They are next to one another in memory!" << endl;

        }

        else 

        {

            cout << "They are not adjacent to one another in memory!" << endl;

        }

    }

    return 0;

}

Cursed

MrD.

g4143