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Program hangs at bitwise multiplication function

Cameron Basham (3)
Hello all! So I'm doing a homework question asking me to code some Egyptian division, but that's not what I need help with. The problem is that I am only allowed to use bitwise operations for the first chunk of the program (until we get to fractions in the remainders).

I'm very new to functions and modularizing, and I just can't seem to get my intMultiply function to work. If you scroll down to my "getBinaryAnswer" function, you'll see one line commented out, and I've temporarily replaced it with a working but "illegal" line. If you have a simpler way to approach that line, I would also love to hear it.

Anyway, final thing on intMultiply. I tested it on its own inside main, and the program would just hang right before it. Is it because I did something wrong in using intAddition within intMultiply? Please help!

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#include <QtCore/QCoreApplication>
#include <iostream>
#include <cstdlib>
#include <iomanip>

using namespace std;

int intAddition(int num1, int num2);
int intMultiply(int num1, int num2);
int getNumbers(int &num1, int &num2);
int getBinaryAnswer(int dividend, int divisor, int &binary, int &ans);

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    int dividend = 0, divisor = 0, counter = 1, binaryAns = 0;
    getNumbers(dividend, divisor);
    getBinaryAnswer(dividend, divisor, counter, binaryAns);
    cout<<endl;
    return a.exec();
}


int intAddition(int num1, int num2)
{
    int carry = 0, sum = 0;
    do
    {
        carry = num1 & num2;
        sum = num1 ^ num2;
        carry <<= 1;
    }while(carry);
    return(sum);
}


int intMultiply(int num1, int num2)
{
    int product = 0, i = 0;
    while(i < num2)
    {
        product = intAddition(num1, product);
        i = intAddition(i, 1);
    }
    return product;
}


int getNumbers(int &dividend, int &divisor)
{
    cout<<"Please enter the dividend."<<endl;
    cin>>dividend;
    cout<<"Please enter the divisor."<<endl;
    cin>>divisor;
    return 0;
}


int getBinaryAnswer(int dividend, int divisor, int &binary, int &ans)
{
    int divisorCounter = divisor;
    while (divisorCounter < dividend)
    {
        binary <<= 1;
        divisorCounter <<= 1;
    }
    while (divisorCounter > divisor)
    {
//     if (intAddition((intMultiply(ans, divisor)),divisorCounter) <= dividend)
       if (intAddition((ans*divisor),divisorCounter) <= dividend)
             ans |= binary;
       binary >>= 1;
       divisorCounter >>= 1;
    }
    cout<<ans;
    return ans;
}
cire (8284)
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int intAddition(int num1, int num2)
{
    int carry = 0, sum = 0;
    do
    {
        carry = num1 & num2;
        sum = num1 ^ num2;
        carry <<= 1;
    }while(carry);
    return(sum);
}


You'll notice that in intAddition carry and sum are assigned the same value in every iteration of the loop (which means the loop will never terminate.)
Cameron Basham (3)
Wow, don't know how I ended up with that! Thanks for looking through and catching that. I didn't even notice because I was (stupidly) using numbers where no bits needed to be carried.

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int intAddition(int num1, int num2)
{
    int carry = 0, sum = 0;
    do
    {
        carry = num1 & num2;
        sum = num1 ^ num2;
        num1 = carry << 1;
        num2 = sum;
    }while(carry);
    return(sum);
}


Much better.
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