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How can I find the number of elements in a hash?

by Malkavian (Friar)
on Mar 08, 2001 at 22:07 UTC ( #63038=categorized question: print w/replies, xml ) Need Help??
Contributed by Malkavian on Mar 08, 2001 at 22:07 UTC
Q&A  > hashes


Is there any fast way of finding the number of elements in a hash without first assigning an array of keys of a hash?
Basically, I don't like the overhead of doing the operation:

@array=keys(%hash); $size=$#array;

It just seems a little wasteful. If anyone can point out a quickie answer, I'd be hideously grateful



Answer: How can I find the number of elements in a hash?
contributed by OeufMayo

The easiest way is to have the keys function evaluated in scalar context:

%hash = ('foo'=>1, 'bar'=>3); $count = keys %hash;
Answer: How can I find the number of elements in a hash?
contributed by Bloodelf

print scalar(keys %h);
Answer: Size of a hash
contributed by japhy

You did that wrong, by the way. You wanted $size = @array, not $#array. And you want to call keys() in scalar context, like it's documented.

Answer: How can I find the number of elements in a hash?
contributed by sot3

Use this: $size = scalar keys %hash;

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