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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Fri, 16 Dec 2011 00:32:11 -0700
Subject: Re: test for list equality
To: Alec Taylor <alec.taylor6@gmail.com>
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On Fri, Dec 16, 2011 at 12:11 AM, Ian Kelly <ian.g.kelly@gmail.com> wrote:
> On Thu, Dec 15, 2011 at 11:30 PM, Alec Taylor <alec.taylor6@gmail.com> wr=
ote:
>> Just for fun, use the Hungarian Algorithm
>>
>> (Python implementation: http://software.clapper.org/munkres/)
>
> That's a pretty silly approach, but okay:
>
> def listequals(a, b):
> =A0 =A0if len(a) !=3D len(b):
> =A0 =A0 =A0 =A0return False
> =A0 =A0matrix =3D [[int(item_a !=3D item_b) for item_b in b] for item_a i=
n a]
> =A0 =A0path =3D Munkres().compute(matrix)
> =A0 =A0return sum(matrix[r][c] for (r, c) in path) =3D=3D 0

Amendment -- it seems that Hungarian implementation fails on an empty matri=
x:

def listequals(a, b):
    if len(a) =3D=3D len(b) =3D=3D 0:
        return True
    if len(a) !=3D len(b):
        return False
    matrix =3D [[int(item_a !=3D item_b) for item_b in b] for item_a in a]
    path =3D Munkres().compute(matrix)
    return sum(matrix[r][c] for (r, c) in path) =3D=3D 0