$input ne 'good' && $input ne 'bad' && $input ne 'iffy'

##</code><code>##

if    ($input eq 'good') {print "..."}
elsif ($input eq 'bad')  {print "..."}
elsif ($input eq 'iffy') {print "..."}
else {next}
last;

##</code><code>##

print "Are you having/had a good, bad, or iffy day $name?: ";
while (my $input = <>) {
    chomp $input;
    if    ($input eq 'good') {print "..."; last}
    elsif ($input eq 'bad')  {print "..."; last}
    elsif ($input eq 'iffy') {print "..."; last}
    print "Are you having/had a good, bad, or iffy day $name?: ";
}

##</code><code>##

while (do {print "...."; defined (my $input = <>)}) {
    if    (...) {...; last}
    elsif (...) {...; last}
    elsif (...) {...; last}
}