HackerRank Python Solution - Strings - Alphabet Rangoli

• You are given an integer, N. Your task is to print an alphabet rangoli of size N. (Rangoli is a form of Indian folk art based on the creation of patterns.)
• Different sizes of alphabet rangoli are shown below:

#size 3

----c----
--c-b-c--
c-b-a-b-c
--c-b-c--
----c----

#size 5

--------e--------
------e-d-e------
----e-d-c-d-e----
--e-d-c-b-c-d-e--
e-d-c-b-a-b-c-d-e
--e-d-c-b-c-d-e--
----e-d-c-d-e----
------e-d-e------
--------e--------

#size 10

------------------j------------------
----------------j-i-j----------------
--------------j-i-h-i-j--------------
------------j-i-h-g-h-i-j------------
----------j-i-h-g-f-g-h-i-j----------
--------j-i-h-g-f-e-f-g-h-i-j--------
------j-i-h-g-f-e-d-e-f-g-h-i-j------
----j-i-h-g-f-e-d-c-d-e-f-g-h-i-j----
--j-i-h-g-f-e-d-c-b-c-d-e-f-g-h-i-j--
j-i-h-g-f-e-d-c-b-a-b-c-d-e-f-g-h-i-j
--j-i-h-g-f-e-d-c-b-c-d-e-f-g-h-i-j--
----j-i-h-g-f-e-d-c-d-e-f-g-h-i-j----
------j-i-h-g-f-e-d-e-f-g-h-i-j------
--------j-i-h-g-f-e-f-g-h-i-j--------
----------j-i-h-g-f-g-h-i-j----------
------------j-i-h-g-h-i-j------------
--------------j-i-h-i-j--------------
----------------j-i-j----------------
------------------j------------------

• The center of the rangoli has the first alphabet letter a, and the boundary has the N^th alphabet letter (in alphabetical order).

Function Description:

• Complete the rangoli function in the editor below.
• rangoli has the following parameters:
• int size: the size of the rangoli
• Returns string: a single string made up of each of the lines of the rangoli separated by a newline character (\n)

Input Format:

• Only one line of input contains size, the size of the rangoli.

Constraints:

• 0 < size < 27

Sample Input:

5

Sample Output:

--------e--------
------e-d-e------
----e-d-c-d-e----
--e-d-c-b-c-d-e--
e-d-c-b-a-b-c-d-e
--e-d-c-b-c-d-e--
----e-d-c-d-e----
------e-d-e------
--------e--------

Solution:

from string import ascii_lowercase as chars
def print_rangoli(size):
    pattern = [(('-'.join(chars[i:n])[::-1]+'-'.join(chars[i:n])[1:])).center(4*n-3, '-') for i in range(n)]
    
    print(*(pattern[::-1]+pattern[1:]), sep="\n")

if __name__ == '__main__':
    n = int(input())
    print_rangoli(n)

Disclaimer: The problem statement is given by hackerrank.com but the solution is generated by the Geek4Tutorial admin. If there is any concern regarding this post or website, please contact us using the contact form. Thank you!