How to merge pdf files using the pdfunite tool on linux

merger.sh

#!/usr/bin/env bash
set -e # Quit on first error

count=0
for i in ./*/*
do 
	my_array["$count"]="$i" # Creates an array with the filenames
	((++count)) # Increase the array index
	echo ${my_array[@]} # Echo the contents of the array
done
# Carryout the merge
pdfunite ${my_array[@]} merged_output.pdf

sample-folder-tree.txt

.
|-- 01
|   `-- introduction-to-google-cloud-platform-slides.pdf
|-- 02
|   `-- getting-started-with-google-cloud-platform-slides.pdf
|-- 03
|   `-- virtual-machines-and-networks-in-the-cloud-slides.pdf
|-- 04
|   `-- storage-in-the-cloud-slides.pdf
|-- 05
|   `-- containers-in-the-cloud-slides.pdf
|-- 06
|   `-- applications-in-the-cloud-slides.pdf
|-- 07
|   `-- developing-deploying-and-monitoring-in-the-cloud-slides.pdf
|-- 08
|   `-- big-data-and-machine-learning-in-the-cloud-slides.pdf
|-- 09
|   `-- summary-and-review-slides.pdf
|-- merged_output.pdf
`-- merger.sh