[Python/Hackerrank] Strings > Alphabet Rangoli

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 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 containing size, the size of the rangoli.

Constraints

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--------

 

문제해석

랑골리(rangoli)라는 것은 인도 전통 미술로 집 마당이나 거실의 바닥을 전통 문양으로 장식하는 것이라고 한다. input으로 N값을 입력받아 알파벳으로 이 랑골리 패턴을 출력해야 한다. 즉, N=3이면 a, b, c까지의 3개 알파벳으로 출력을 해야 한다. 랑골리의 가운데는 항상 첫번째 문자인 a가 들어가고 그 다음은 알파벳 순서대로 출력이 된다. 

 

문제풀이

def print_rangoli(size):
    # your code goes here
    alp = 'abcdefghijklmnopqrstuvwxyz'
    for i in range(size-1,-size,-1):
        rangoli = '-'.join(alp[size-1:abs(i):-1]+alp[abs(i):size])
        print(rangoli.center(4*size-3,'-'))

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