[Tutor] Help

[Alan Gauld]

On 07/10/2020 21:16, Gilbert Makgopa wrote:

> def sum_divisors(n):
>   sum = 0
>   div =0
>   # Return the sum of all divisors of n, not including n
>   while (div > 0 and div!=n):
>     sum = sum + div
>     return sum
> 
> print(sum_divisors(0))
> # 0
> print(sum_divisors(3)) # Should sum of 1
> # 1
> print(sum_divisors(36)) # Should sum of 1+2+3+4+6+9+12+18
> # 55

Where within your function do you check to see if div is actually a
divisor? In fact your function is severely broken and will always
return None (the default return value of a Python function). If
you are getting other results you must be running different
code to what you posted.

Things wrong:
1) You start with div=0 then immediately check if div > 0 which
it isn't.
2) You never modify div or n so the while loop always gives
the same result.
3) You never check if div is actually a diviror of n before
adding it to sum.


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Alan G
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