++ is the auto-increment operator.
$hash{$line} is a hash assignment

So $hash{$line}++ auto-increments the value of $hash{$line}

Also please read Writeup Formatting Tips and use <code> tags around your code

grep
One dead unjugged rabbit fish later...

In reply to Re: Question about ++ and hash value by grep
in thread Question about ++ and hash value by ada

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