in the sample input it is said that we have to take 2 numbers and in the explanation of problem 2 strings are taken what we have to take
Ultra fast mathematician
@Learning_bunny Actually these are binary numbers so you have to take them in string as if you take them int so compiler take that number in octal form,also you have to do work on each digit of number so taking string is best option.Hope you get it.Feel free to ask any doubt 
I hope I’ve cleared your doubt. I ask you to please rate your experience here
Your feedback is very important. It helps us improve our platform and hence provide you
the learning experience you deserve.
On the off chance, you still have some questions or not find the answers satisfactory, you may reopen
the doubt.