perl -wMstrict -le 'print qq{perl version: $] \n};;; my $x; my %y= ("h"=>1, "i"=>2);  print $x, $y{x}; printf "%s", $x;'

##</code><code>##

perl version: 5.018002

Use of uninitialized value $x in print at -e line 1.
Use of uninitialized value in print at -e line 1.

Use of uninitialized value $x in printf at -e line 1.
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