How to check if a list has duplicate numbers in Python

Question

So I have a list called puzzle which contains the follow lists:

puzzle = [[1, 3, 5, 5, 4],
[3, 5, 1, 3, 4],
[2, 3, 4, 5, 1],
[1, 5, 3, 2, 2],
[5, 4, 1, 3, 2]]

I would like to check each list inside puzzle and test if there are any duplicate numbers that are not zero, in which case the code would return false. How can I do this?

more complex: you have to rule out zero. Well, that's not that difficult once you have sorted out the duplicates, you're right on that point. — Jean-François Fabre, Feb 16 '17 at 21:54
@Daniel: the non-zero thing is not handled in the duplicate thing. — Jean-François Fabre, Feb 16 '17 at 22:01

score 0 · Answer 1 · answered Feb 16 '17 at 21:58

0

Almost the same approach -- except that you'd run it on a sub-list without zeros in it.

def has_dup(lst):
    no_zeros = [x for x in lst if x != 0]
    return len(set(no_zeros)) != len(no_zeros)

is_valid = any(has_dup(x) for x in puzzle)

answered Feb 16 '17 at 21:58

UltraInstinct

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How to check if a list has duplicate numbers in Python

1 Answers1