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How to check similarity of two hash tables

( #157719=categorized question: print w/ replies, xml ) Need Help??
Contributed by Rajiv on Apr 09, 2002 at 13:44 UTC
Q&A  > hashes


Description:

Perl Monks, Please Suggest: How can i find whether two hash tables have same and equal number of keys.

Answer: How to check similarity of two hash tables
contributed by RMGir

Of course, the obligatory one-liner (ok, one-expression) version:

my $areEqual = (keys %hash1 == keys %hash2) && 0 == grep {!exists $hash2{$_}} keys %hash1;
Answer: How to check similarity of two hash tables
contributed by RMGir

They're equal if, as you say, they have the same number of keys AND all the keys in one are in the other.

my $areEqual=1; if(keys %hash1 == keys %hash2) { foreach my $key(keys %hash1) { if(!exists $hash2{$key}) { $areEqual=0; last; } } } if($areEqual) { print "ARE "; } else { print "ARE NOT "; } print "equal\n";

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