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How to get number of entries in a hash with values less than n?

Below I use $size = keys %prices; to get the total number of entries in a hash. However, is there a way in the example below to get the number of entries with price less than $4?

use strict;

my %prices;

# create the hash
$prices{'pizza'} = 12.00;
$prices{'coke'} = 1.25;
$prices{'sandwich'} = 3.00;
$prices{'pie'} = 6.50;
$prices{'coffee'} = 2.50;
$prices{'churro'} = 2.25;

# get the hash size
my $size = keys %prices;

# print the hash size
print "The hash contains $size elements.\n";
Solution

  • Yes, you can run a grep filter on the values of the hash to quickly calculate this.

     $num_cheap_items = grep { $_ < 4 } values %prices;
 @the_cheap_items = grep { $prices{$_} < 4 } keys %prices;