Hello I need your help:D Can anyone explain this code ?

Question

a= ; #fill in the blanks!
roots=[x for x in range(1,a) if a%x ==o];
print(sum(roots)==a and a>0

Answer 1

Looks like a perfect number checker to me. But needs some fixing ;)

a = 6 # try 6, 28, 496 or 8128
roots = [x for x in range(1, a) if a%x == 0]
print(sum(roots) == a and a > 0)

roots is constructed by a list comprehension - this is the expression inside the square brackets. It tells Python to create this list by iterating from 1 to a (6 in this example) and an only those elements which a is divisible by (so the remainder of such a division a%x is zero) - 1, 2 and 3 in our example.

Then it prints a result of a logical test of:
1. sum of roots elements equals to a
and
2. a > 0

This logical test will be True only if a is a perfect number (the definition is that a perfect number is equal to the sum of all its divisors but the number itself).

You can check out my code on perfect numbers, too :)
https://code.sololearn.com/cz9goi77Ls5L/?ref=app

Answer 2

thank you, that was very helpful!