Menu
How do I find the number of keys in a hash, like using $# for arrays?
894
But a good general “rule of thumb” is: The hash table should be an array with length about 1.3 times the maximum number of keys that will actually be in the table, and. Size of hash table array should be a prime number.
Answer: The hashing key is the raw data in which to be hashed. The hashing algorithm is the algorithm which performs a function to convert the hash key to the hash value. the hash value is what is produced as a result of the hash key being passed into the hashing algorithm.
From perldoc perldata: If you evaluate a hash in scalar context, it returns false if the hash is empty. If there are any key/value pairs, it returns true; more precisely, the value returned is a string consisting of the number of used buckets and the number of allocated buckets, separated by a slash.
keys() function in Perl returns all the keys of the HASH as a list. Order of elements in the List need not to be same always, but, it matches to the order returned by values and each function. Syntax: keys(HASH) Parameter: HASH: Hash whose keys are to be printed.
scalar keys %hash or just
keys %hash if you're already in a scalar context, e.g. my $hash_count = keys %hash or print 'bighash' if keys %hash > 1000.
Incidentally, $#array doesn't find the number of elements, it finds the last index. scalar @array finds the number of elements.
57
we can use like this too
my $keys = keys(%r) ; print "keys = $keys" ; 0+(keys %r) If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With