Two divisible lists-CodePudding

Im facing a question in Python where I need the function to return True if all the numbers of List1 can be divisible by ANY number in List2. I tried to use the all function for this like :

for num1 in List1: 
    if all(num1 % num2 == 0 for num2 in List2)
    return True

but the problem with this is that it check if ALL the numbers in list 1 can be divisible by ALL the numbers in list2. Im wondering if there is a way to combine the all and the any functions to do this problem?

CodePudding user response：

You're almost there. List comprehensions can contain an arbitrary number of variables, in which case all combinations of them will be considered. You can simply say

return all(l1_elm % l2_elm == 0 for l1_elm in List1 for l2_elm in List2)

This is equivalent to

for l1_elm in List1:
    for l2_elm is List2:
        # if this doesn't evaluate to 0
        if l1_elm % l2_elm:
            return False
return True

By the way, it's idiomatic in python to use snake_case for variables and PascalCase for classes, so your List1 and List2 should ideally be written as list_1 (or just list1) and list_2, respecitively.

@ThePyGuy also makes a good point. The modulo operator fails if the second argument is 0 with ZeroDivisionError: integer division or modulo by zero. If you expect that List2 might contain a 0 value, you should also check for that before attempting to divide, i.e. modify the condition to if l2_elm == 0 or l1_elm % l2_elm.

CodePudding user response：

You can combine all and any in a comprehension:

>>> l1=[8,10,20]
>>> l2=[2,3,0]
>>> any(all(n1%n2==0 for n1 in l1) for n2 in l2)
True

CodePudding user response：

I think @ThePyGuy is right but here was my attempt before I saw his post:

List1 = [1,2,3,4,5,6]
List2 = [7,8,9,10,11,12]

def testlist():
    for num2 in List2:
        if all(List1) % num2 == 0:
            return True
        else:
            return False
evaluate = testlist()
print(evaluate)