Divsion by Subtraction

[DoctorBob]

Hello.. I finished a program that does multiplication by successive addition.. But now I want to change my program to do division by successive subtraction? I tried to change my while loop to break out sooner but it didn't work... Thanks for any Help!

#include<iostream>
using namespace std;

int div(int m, int n){
  int sum = 0;
  while(n != 0){
    sum = m - sum;
    n = n - 1;
  }
  return sum;
}

int main(){
  int m, n;
  cout<<"Enter two numbers: ";
  cin>>m>>n;
  cout<<div(m,n)<<endl;
  return 0;
}

[VernonDozier]

I think your algorithm has some problems. In this line:

while(n != 0)

you are already deciding how many times you are going through the loop. n has been passed to div. So if n was 5, you're going to go through the loop 5 times? Not true. You don't know how many times you are going to go through the loop. That's what you are trying to find out. Set a loop counter to start at 0. Increment it every pass through the loop. The loop control should be something like:

while (m >= 0)

n will be subracted from m each time through the loop. Your loop counter will be incremented each time (you'll have to create a variable other than m or n for that loop counter). The loop counter will be what is returned from the function div.

[Colin Mac]

Division by subtraction is how many times a number can be subtracted from a number until
you're left with nothing.

eg 6/3 = 2. Three can be subtracted from six twice.

Therefore you should be incrementing a value from zero, after each subtraction.

while( num != 0)
{
     num = num - num2;
     result++;
}

This will only work as long as the numbers can be divided evenly, so you'll need to come up with something better if odd numbers are entered.