Difference between this C++ function and Python function

Question

I have function in C++ that returns positive number a magnified b times. In C++ this function runs with no errors but I want to use this function in Python. Could anyone tell why this function returns result in C++ but does not return it in Python or where I made a mistake in Python code?

I know that I can write this function in many other ways and that this function may not be the best solution but what is wrong with THIS particular example? What I have to do to run this in Python without writing new, better function obviously. Why I can run this code in C++ but not in Python?

C++ CODE:-

int exp(int a,int b){
    int result=1;
    while(b!=0){
        if(b%2==1){
          result*=a;
        }
        b/=2;
        a*=a;
    }
    return result;
}

PYTHON CODE:-

def exp(a,b):
  result=1
  while b!=0:
    if b%2==1:
      result*=a
    b/=2
    a*=a
  return result

Is something wrong with while condition in Python???

`b /= 2` -- not integer divide in Python 3; compare to `b //= 2`. See https://stackoverflow.com/q/183853/2864740 — user2864740, May 18 '19 at 22:21

score 2 · Accepted Answer · answered May 18 '19 at 22:23

2

You're using floating point division in the Python code:

b/=2

You want integer division:

b //= 2

answered May 18 '19 at 22:23

Paul Evans

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Only for python 3.x as previous versions worked well with `/` and treated it's output as integer. – Vasu Deo.S May 18 '19 at 22:25
@VasuDeo.S Question tagged with python3. – haccks May 18 '19 at 22:26
I was just trying to inform the readers of this answer, if they are not aware of this fact. – Vasu Deo.S May 18 '19 at 22:28
Yes I am using python-3.x now, anyway thanks all of u guys, it helped. That was really simple. – Hubertto May 18 '19 at 22:51

Difference between this C++ function and Python function

1 Answers1