sub f ($) { my $x = shift; return sqrt(abs($x) + 5*($x**3)); } my @a; $a[$_] = <> for (0..10); for (my $i = @a; $i >= 0; $i--) { my $y = f($a[$i]); print "$i too large\n" if $y > 400; print "$i: $y\n" unless $y > 400; }