How to get minimum values key from hash in Perl

Question

I have script which is able to pick minimum value from hash values.

use strict;
use warnings;

use Data::Dumper;
use List::Util qw(min);

my @array = qw/50 51 52 53 54/;

my $time = 1596561300;

my %hash;

foreach my $element(@array){  
    $hash{$time} = $element;
    $time += 6; #based on some condition incrementing the time to 6s
}

print Dumper(\%hash);

my $min = min values %hash; 
print "min:$min\n";

Here I am able to get 50 as a minimum value out of all the values in hash values. But how would I also get the hash key that corresponds to the minimum value, i.e.,1596561300.

Answer 1

From the key, you can get the value. So you want the key with the minimal associated value.

min LIST can be written as reduce { $a <= $b ? $a : $b } LIST, so we can use

use List::Util qw( reduce );

my $key = reduce { $hash{$a} <= $hash{$b} ? $a : $b } keys %hash;
my $val = $hash{$key};

or

my ($key) = keys(%hash);
my $val = $hash{$key};
for (keys(%hash)) {
   if ($hash{$_} < $val) {
      $key = $_;
      $val = $hash{$val};
   }
}