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perl -wle 'my @a=1..9; printf"$a[%d]\n", 4' perl -wle 'my @a=1..9; printf"$a[%2d]\n", 4' perl -wle 'my @a=1..9; printf"\$a[%d]\n", 4'
perl -wle 'my @a=1..9; printf"%d\n", $a[4]'