my( $x_lo, $x_hi ) = ( -180, -170 );
my( $y_lo, $y_hi ) = ( -130, -120 );

my @matches = 
  grep { $_->[0] >= $x_lo && $_->[0] <= $x_hi
      && $_->[1] >= $y_lo && $_->[1] <= $y_hi } 
  map [ split ], <>;