The challenge

Write an algorithm that takes an array and moves all of the zeros to the end, preserving the order of the other elements.

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move_zeros([1, 0, 1, 2, 0, 1, 3]) # returns [1, 1, 2, 1, 3, 0, 0]

The solution in Python code

Option 1:

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def move_zeros(arr):
    l = [i for i in arr if isinstance(i, bool) or i!=0]
    return l+[0]*(len(arr)-len(l))

Option 2:

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def move_zeros(array):
    return sorted(array, key=lambda x: x==0 and type(x) is not bool)

Option 3:

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def move_zeros(array):
     return [a for a in array if isinstance(a, bool) or a != 0] + [a for a in array if not isinstance(a, bool) and a == 0]

Test cases to validate our solution

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import test
from solution import move_zeros

@test.it("Basic tests")

test.assert_equals(move_zeros(
    [1, 2, 0, 1, 0, 1, 0, 3, 0, 1]),
    [1, 2, 1, 1, 3, 1, 0, 0, 0, 0])
test.assert_equals(move_zeros(
    [9, 0, 0, 9, 1, 2, 0, 1, 0, 1, 0, 3, 0, 1, 9, 0, 0, 0, 0, 9]),
    [9, 9, 1, 2, 1, 1, 3, 1, 9, 9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0])
test.assert_equals(move_zeros([0, 0]), [0, 0])
test.assert_equals(move_zeros([0]), [0])
test.assert_equals(move_zeros([]), [])