C++ program -Math Tutor

Question

I have a HW assignment that is to make a program that will allow a user to select either to add or subtract a random number from 1-500. The user types in their answer and if correct they will receive a congratulations messaged on screen. If incorrect they will receive a message stating "incorrect the correct answer is:". I have written the code and it works but on the subtract function when I test it and get the question wrong on purpose it gives me a message saying the correct answer is and instead of subtracting the numbers properly it adds them. I have tried everything to fix it but no luck. Does anyone know what could be wrong? That is the only thing not working.

#include <iostream>

#include <ctime>

#include <cstdlib>

using namespace std;

int main()

{

//1. Variables

srand(time(0));

int num1 = rand() % 500 + 1;

int num2 = rand() % 500 + 1;

int answer = 0;

int answer2 = 0;

int correctanswer = num1 + num2;

int correctanswer2 = num1 - num2;

int choice = 0;

//2. Talk to the user/Decision

cout << "Would you like to ADD(1) or SUBTRACT(2)?" << endl;

cin >> choice;

if (choice == 1)

{

cout << "Please Answer The Following:" << endl;

cout << num1 << "+" << num2 << "=";

cin >> answer;

}

else if (choice == 2)

{

cout << "Please Answer The Following:" << endl;

cout << num1 << "-" << num2 << "=";

cin >> answer2;

}

//3. Store the variables

if (answer == num1 + num2)

{

cout << "Congratulations! You are correct!" << endl;

}

else if (answer2 == num1 - num2)

{

cout << "Congratulations! You are correct!" << endl;

}

else if (answer != num1 + num2)

{

cout << "Incorrect, the correct answer is:" << endl;

cout << correctanswer;

}

else if (answer2 != num1 - num2)

{

cout << "Incorrect, the correct answer is:" << endl;

cout << correctanswer2;

}

}

Answer 1

using namespace std;

#include <iostream>

#include <time.h>

#include <stdlib.h>

int Go()

{

srand(time(0));

int num1 = rand() % 500 + 1;

int num2 = rand() % 500 + 1;

int iResponse;

int iCorrectAnswer;

int op=-1;

while ((op!=1) && (op!=2))

{

cout << "Please input 1 for Addition OR 2 for Subtraction :>";

cin >> op;

}

switch (op)

{

case 1:

{

iCorrectAnswer = num1 + num2;

cout << "What is: " << num1 << " + " << num2 << " = ??? ";

break;

} //case1

case 2:

{

//Do you want to GUARANTEE a positive answer by ensuring the num1 > num2 ???

// if so, uncommment the next line which swaps them if they are out of order....

//if (num1<num2) { int iTemp=num1; num1 = num2; num2=iTemp; }

iCorrectAnswer = num1 - num2;

cout << "What is: " << num1 << " - " << num2 << " = ??? ";

break;

}

} //switch

cin >> iResponse;

if (iCorrectAnswer ==iResponse)

{

cout << "Congratulations! You are correct!" << endl;

}

else

{

cout << "Sorry that is incorrect. The correct answer is " << iCorrectAnswer << endl;

}

} //Go

int main()

{

Go();

}