elsif (
  $input ne 'good' and
  $input ne 'bad' and
  $input ne 'iffy'
){
next;
}

[download]
or: 
elsif (
 $input !~ /good|bad|iffy/
){
next;
}

[download]
or consider a lookup hash: 
my %lookup = (
  good => undef,
  bad  => undef,
  iffy => undef,
);
# and then within your loop
next unless exists $lookup{$input};

[download]

update: added a missing brace
update 2: changed =~ to !~ in second snippet

In reply to Re: A better understanding of while () loops by wfsp
in thread A better understanding of while () loops by sub_chick

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