Can i have explanations as directive ?

Question

Speeling backwards

Given a string as input, use recursion to output each letter of the strings in reverse order, on a new line.

Sample Input
HELLO

Sample Output
O
L
L
E
H

Answer 1

Given the string

s = 'HELLO'

the individual characters can be obtained through the use of an index

print(s[0])
// Outputs 'H'

The problem requires you to use recursion, so that's tricker than just looping and printing the letters from the back.

A possible implementation would be to have a function which takes an input string, pop the last character of the string, and pass the remaining string to a recursive call. E.g.

recur('HELLO') // output 'O'
recur('HELL') // output 'L'
recur('HEL') // output 'L'
... etc

You'll need some knowledge on getting substrings out of strings:
https://stackoverflow.com/questions/663171/how-do-i-get-a-substring-of-a-string-in-JUMP_LINK__&&__python__&&__JUMP_LINK

Answer 2

Thanks Rei