sub too_many_repetitions { my( $word )= @_; my $same_char_percent= 0.5; my $max_same_char= $same_char_percent * length $word; my @chars= split // => $word; my %seen; $seen{$_}++ for @chars; return 1 if $max_same_char < pop @{[sort values %seen]}; } print $_, ' => ', too_many_repetitions($_), $/ for qw(abcdef aaaaaa abcabc); __END__ abcdef => aaaaaa => 1 abcabc =>