Task 1: Good Pairs

You are given a list of integers, @list.

Write a script to find the total count of Good Pairs: A pair (i, j) is
called good if list[i] == list[j] and i < j.


Example 1

Input: @list = (1,2,3,1,1,3)
Output: 4

There are 4 good pairs found as below:
(0,3)
(0,4)
(3,4)
(2,5)

Example 2

Input: @list = (1,2,3)
Output: 0

Example 3

Input: @list = (1,1,1,1)
Output: 6

Good pairs are below:
(0,1)
(0,2)
(0,3)
(1,2)
(1,3)
(2,3)

MY NOTES: very easy.  two nested for loops..

GUEST LANGUAGE: As a bonus, I also had a go at translating ch-1.pl
into C (look in the C directory for the translation)


Task 2: Good Triplets

You are given an array of integers, @array and three integers $x,$y,$z.

Write a script to find out total Good Triplets in the given array.

A triplet array[i], array[j], array[k] is good if it satisfies the following conditions:

a) 0 <= i < j < k <= n (size of given array)
b) abs(array[i] - array[j]) <= x
c) abs(array[j] - array[k]) <= y
d) abs(array[i] - array[k]) <= z

Example 1

Input: @array = (3,0,1,1,9,7) and $x = 7, $y = 2, $z = 3
Output: 4

Good Triplets are as below:
(3,0,1) where (i=0, j=1, k=2)
(3,0,1) where (i=0, j=1, k=3)
(3,1,1) where (i=0, j=2, k=3)
(0,1,1) where (i=1, j=2, k=3)

Example 2

Input: @array = (1,1,2,2,3) and $x = 0, $y = 0, $z = 1
Output: 0



MY NOTES: not quite so easy, start with 3 nested for loops;-)

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