my $count = 0;
for ( sort { $a cmp $b } keys %hash ) {
  print "$_ => $hash{$_}\n"
    if $count++ < 10;
}
[download]

or by value...

my $count = 0;
for ( sort { $hash{$a} cmp $hash{$b} } keys %hash ) {
  print "$_ => $hash{$_}\n"
    if $count++ < 10;
}
[download]

Assuming you want ascending order. Swap $a and $b inside the sord block if you want descending. Change the 10 to the number of "first" values you want

If you had posted your code inside <code>...</code> tags, it would have been formated correctly.

Update: See also How do I sort a hash (optionally by value instead of key)? in perlfaq4

Update^2: Thanks to shmem for help with the link

I want to sort that hash, and print only the values for the first keys

my %smallest;
for my $k (keys %hash) {
  my $v = (sort { $a <=> $b } @{$hash{$k}})[0]; # assuming numeric val
+ues
  $smallest{$k} = $v;
}
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You cannot sort a hash. You can only sort the hash keys. The function for sorting things is called, unimaginatively, sort.

Where exactly do you have problems?

Thats what i meant, sort has keys

The probleme is how to print only the first value in the hash

• Make a sorted list of keys.
• print using the first of the keys.
• Make that the last thing you do in your loop.
• Profit!

(Or simply use an array slice to pull off my $first_key = (sort keys %foo)[0] and just use that instead of setting up a loop . . .)

The cake is a lie.
The cake is a lie.
The cake is a lie.

So you want the first entry of the key/value set in your @array, where each entry in the @array is a comma separated list of key/val?

my %hash = map { @_ = split /,/, $_; $_[0] => $_[1] } @array;
my $first_key = (sort keys %hash)[0];
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You might not want to code it quite so compactly in a real app, but you should get the gist of it - turn into a hash, then take the first key from sorting the keys.

Is that what you mean?