Ah, kvale has beaten me to the regex solution. Ok, I will post a slightly different one...
#!/usr/bin/perl -w

# vim: set tabstop=3

use strict;

while (<DATA>)
{
    chomp;
    print "$_ .. ";

    if (m/^((?=.*?[A-Z])(?=.*?[a-z])(?=.*?[0-9]).*)$
          (??{ ! exists %{{qw! 5 0 6 0 7 0 8 0 !}}->{length($1)} })/x)
    {
        print "valid\n"
    } else {
        print "invalid\n"
    }
}


__DATA__
1245Za78
1245Za7b8
45a7b8
a78Z
12Three
kMdlOz
6KYX
diImMU1Y
ZNw4uWSht
jDqvSN
qVRR
le2WTQv
us1j3SerC
OZv0LtSJ
9qyscg
LbX7o74
80TeRHq
7YIiXnEV8
e1Yctl9
8iGoc
R87MeDCFz
ziTnlk
cziP

[download]

In reply to Re: regex elegance contest - validate a pw by Roger
in thread regex elegance contest - validate a pw by tos

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