Task 1: Unique Array

You are given list of arrayrefs.
Write a script to remove the duplicate arrayrefs from the given list.

Example 1

Input: @list = ([1,2], [3,4], [5,6], [1,2])
Output: ([1,2], [3,4], [5,6])

Example 2

Input: @list = ([9,1], [3,7], [2,5], [2,5])
Output: ([9, 1], [3,7], [2,5])

MY NOTES: nice and easy, only challenge is how to store a representation
of an entire array as a hash key: obvious option is to join(',',@items)

GUEST LANGUAGE: As a bonus, I also had a go at implementing ch-1.pl
into C (look in the C directory for that).  It's not a direct translation
of the Perl solution because that involves sets of joined strings, instead
it does it the obvious low-tech way: finding duplicate arrays and deleting
them.


Task 2: Date Difference

You are given two dates, $date1 and $date2 in the format YYYY-MM-DD.
Write a script to find the difference between the given dates in terms on years and days only.

Example 1

Input: $date1 = '2019-02-10'
       $date2 = '2022-11-01'
Output: 3 years 264 days

Example 2

Input: $date1 = '2020-09-15'
       $date2 = '2022-03-29'
Output: 1 year 195 days

Example 3

Input: $date1 = '2019-12-31'
       $date2 = '2020-01-01'
Output: 1 day

Example 4

Input: $date1 = '2019-12-01'
       $date2 = '2019-12-31'
Output: 30 days

Example 5

Input: $date1 = '2019-12-31'
       $date2 = '2020-12-31'
Output: 1 year

Example 6

Input: $date1 = '2019-12-31'
       $date2 = '2021-12-31'
Output: 2 years

Example 7

Input: $date1 = '2020-09-15'
       $date2 = '2021-09-16'
Output: 1 year 1 day

Example 8

Input: $date1 = '2019-09-15'
       $date2 = '2021-09-16'
Output: 2 years 1 day

MY NOTES: Should be a simple task for Date::Simple or Date::Manup.

GUEST LANGUAGE: As a bonus, I also had a go at translating ch-2.pl
into C (look in the C directory for that).