# Declare package 'Leap'
package Leap;
use strict;
use warnings;
use Exporter qw<import>;
our @EXPORT_OK = qw<is_leap_year>;

sub is_leap_year {
  my ($year) = @_;
  return 0 if $year %   4; # year is not divisible by 4
  return 1 if $year % 100; # year is divisible by 4 but not 100
  return 0 if $year % 400; # year is divisible by 4 and 100 but not 400
  return 1;                # divisible by 400
}

1;