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( #3333=superdoc: print w/replies, xml ) Need Help??
If you're going to do this repeatedly (e.g. first find all the keys with value 'a', then find all keys with value 'b', etc.), then it might help to create a hash that maps the values to keys.
my %val_by_key = ( 1 => 'a', 2 => 'b', 3 => 'a', 4 => 'c', ); my %keys_by_val foreach my $k (keys %vals_by_key) { my $v = $vals_by_key{$k}; push @{ $keys_by_val{$v} }, $k; } # a: 1, 3 print('a: ', join(', ', @{$keys_by_val{'a'}}), "\n"); # a: 1, 3 # b: 2 # c: 4 foreach my $v (keys %keys_by_val) { print("$v: ", join(', ', @{$keys_by_val{$v}}), "\n"); }

In reply to Re: How to get Keys from hash having same value? by ikegami
in thread How to get Keys from hash having same value? by isha

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