### https://theweeklychallenge.org/blog/perl-weekly-challenge-236/
"""

Task 2: Array Loops

Submitted by: [46]Mark Anderson

   You are given an array of unique integers.

   Write a script to determine how many loops are in the given array.

     To determine a loop: Start at an index and take the number at
     array[index] and then proceed to that index and continue this until
     you end up at the starting index.

Example 1

Input: @ints = (4,6,3,8,15,0,13,18,7,16,14,19,17,5,11,1,12,2,9,10)
Output: 3

To determine the 1st loop, start at index 0, the number at that index is 4, proc
eed to index 4, the number at that index is 15, proceed to index 15 and so on un
til you're back at index 0.

Loops are as below:
[4 15 1 6 13 5 0]
[3 8 7 18 9 16 12 17 2]
[14 11 19 10]

Example 2

Input: @ints = (0,1,13,7,6,8,10,11,2,14,16,4,12,9,17,5,3,18,15,19)
Output: 6

Loops are as below:
[0]
[1]
[13 9 14 17 18 15 5 8 2]
[7 11 4 6 10 16 3]
[12]
[19]

Example 3

Input: @ints = (9,8,3,11,5,7,13,19,12,4,14,10,18,2,16,1,0,15,6,17)
Output: 1

Loop is as below:
[9 4 5 7 19 17 15 1 8 12 18 6 13 2 3 11 10 14 16 0]
     __________________________________________________________________

   Last date to submit the solution 23:59 (UK Time) Sunday 1st October
   2023.
     __________________________________________________________________

SO WHAT DO YOU THINK ?
"""
### solution by pokgopun@gmail.com

def countLoop(tup):
    count = 0
    for i in range(len(tup)):
        j = i
        #lst = []
        while True:
            j = tup[j]
            #lst.append(j)
            if j < i: break
            if j == i:
                count += 1
                #print(lst)
                break
    return count

for inpt, otpt in {
        (4,6,3,8,15,0,13,18,7,16,14,19,17,5,11,1,12,2,9,10): 3,
        (0,1,13,7,6,8,10,11,2,14,16,4,12,9,17,5,3,18,15,19): 6,
        (9,8,3,11,5,7,13,19,12,4,14,10,18,2,16,1,0,15,6,17): 1,
        }.items():
    print(countLoop(inpt)==otpt)