Wow. You came up with the exact same thing as I did, except for two little syntax differences. This is what I had. If I had knon that I didn't need the curly's on the grep, and if you reversed the order in your evaluations, they would be the same.

use strict;
my $x = 4;
my $y = 38;
my @z = ( 1, 3, 38, 83 );


print "Yes\n" if ((grep{$_<$x}@z)==(grep{$_<$y}@z));
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