Question

I should define a function overlapping() that takes two lists and returns True if they have at least one member in common, False otherwise. For the sake of the exercise, I should write it using two nested for-loops. What am I doing wrong?

def overlapping(a,b):
    for char in a:
        for char2 in b:
            return char in char2

Any suggestions how to make it work?

Answer 1

If you really need to use 2 loops:

def overlapping(a,b):
    for char1 in a:
        for char2 in b:
            if char1 == char2: return True
    return False

But the solution with sets is much better.