use Modern::Perl;

while (<DATA>) {
    chomp;
    say "$_ : ",
        ( /^0+$/   or /^1+$/ )   ? 'PASS'
      : ( /^0+1+$/ or /^1+0+$/ ) ? 'CLEAN'
      :                            'FAIL';
}

__DATA__
000000
111111
000011111
1111111000
10001001110000011

##</code><code>##

000000 : PASS
111111 : PASS
000011111 : CLEAN
1111111000 : CLEAN
10001001110000011 : FAIL