C++ Calculator Help plz

Hi guys.

I just learned C++, and to see if I have learned anything, I decided to code a calculator program all by myself. I am using xcode on Mac OS X 10.5, and I have coded this so far,

Code:

---

#include <iostream>
using namespace std;
 
int main() //Calculator program!!!!
{
        int add, subtract, multiply, divide, add1, add2, addAnswer, subtract1, subtract2, subtractAnswer, multiply1, multiply2, multiplyAnswer, divide1, divide2, divideAnswer;
        cout << "Please choose the operation!";
        if (cin >> add)
        {
       
        cout << "Enter first addend!";
        cin >> add1;
       
        cout << "Enter second addend!";
        cin >> add2;
       
        addAnswer = (add1 + add2);
        cout << "Answer is " << addAnswer << "!";
        }
       
        if (cin >> subtract)
        {
       
        cout << "Enter first minuend!";
        cin >> subtract1;
       
        cout << "Enter second subtrahend!";
        cin >> subtract2;
       
        subtractAnswer = (subtract1 - subtract2);
        cout << "Answer is " << subtractAnswer << "!";
        }
       
        if (cin >> multiply)
        {
       
        cout << "Enter first multiple!";
        cin >> multiply1;
       
        cout << "Enter second multiple!";
        cin >> multiply2;
       
        multiplyAnswer = (multiply1 * multiply2);
        cout << "Answer is " << multiplyAnswer << "!";
        }
       
        if (cin >> divide)
        {
       
        cout << "Enter first dividend!";
        cin >> divide1;
       
        cout << "Enter second divisor!";
        cin >> divide2;
       
        divideAnswer = (divide1 / divide2);
        cout << "Answer is " << divideAnswer << "!";
        }
return 0;
}

---

I did cmd apple r to get to the console menu, then built and go. It says

"Please choose the operation!"
then I say add or something, then it says

"The Debugger has exited with status 0."

Can you find a problem? I need to fix it so I can learn from my mistake. This is for my learning purposes! Thx

Code:

---

        int add, ... ;
        if (cin >> add)

---

This doesn't do what you think it does. Look up how to use std::cin.

I've seen this before. if I didnt add,

Code:

---

using namespace std

---

then I didn't have to use

Code:

---

std::cin

---

just

Code:

---

cin

---

What is the difference? I'm new at this....

Exit status 0 means that it did exactly what you wanted with no errors and just exited the program. It is so fast though that you cant see the output before it exits the program. I am not sure how a console application in Mac will act when it is finishes, but if it is anything like a Windows based Console app, it will do what you ask it to and then just quit. You are going to have to put something to make it pause so that you can see the output. Try a cin right at the very end asking the user if they want to quit? This will create a pause situtation till you hit a key, then you can see what was printed on the screen.


Right before your return 0; Put a char temp >> cin statement. This will let you see the output till you hit any key, then it will quit the program with your return 0;.

But in my code, if you type in "add", then another cin should pop up, the "Enter First Addend"

I think their is something is wrong with the "if" line.

I dunno

lol. I just skimmed through your code... yes, you are right.

You need something like

string userResponce;
cin >> userResponce;

if (userResponce == "add")
............

and so forth.

Quote:

---

Originally Posted by Caldark

I think their is something is wrong with the "if" line.

---

You're right. When

Code:

---

cin >> add

---

fails to read an integer, such as when you type "add" at the prompt, the expression returns false, and the blocks do not get executed. This is why your program does nothing.
Try reading your input into a string variable.