+ 2

I've been trying the Spy life code coach question. But I just can't seem to get it right. What is wrong with my code?

word = input() rev_word = word[::-1] rev_word = list(rev_word) valid = "a b c d e f g h i j k l m n o p q r s t u v w x y z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z" valid = list(valid) for i in rev_word: if not i in valid: rev_word.remove(i) rev_word = "".join(rev_word) print(rev_word)

21st Jul 2022, 3:50 PM
Umar Muhammad
Umar Muhammad - avatar
7 odpowiedzi
+ 8
Umar Muhammad , the task description says that we have to remove all "none" alphabet character. as Jayakrishna🇮🇳 already mentioned, iterating and removing elements at the same time can create issues. so we can go for an other strategy and try this (we are going to create a new string that contains only allowed characters): > input the string and then reverse it > create an empty list that can hold the characters after "filtering" out not allowed characters > run a loop over the reversed string, it will give you one character in each iteration cycle > check if the character is allowed: this can be done by using the string method isxxxx() that checks for alphabet characters, check also if character is a space if char is alpha or a space, append this character to the list > if iteration of the loop is done, the list contains only allowed characters > finally we have to join the list elements to a string and the output it.
21st Jul 2022, 4:39 PM
Lothar
Lothar - avatar
+ 4
Umar Muhammad , your solution is perfect 👍😁
22nd Jul 2022, 12:28 PM
Lothar
Lothar - avatar
+ 3
in loop, for I in rev_word: you are using original list, so removing will reflect on next iteration value. a1cb => if you remove 1, next element is for i value is b, not c because list str is acb.
21st Jul 2022, 4:02 PM
Jayakrishna 🇮🇳
+ 3
Lothar thank you. I'll try these
21st Jul 2022, 4:42 PM
Umar Muhammad
Umar Muhammad - avatar
+ 3
As @Lother said, use isalpha() , (isspace() ) instead of 'valid' list. If true add to empty list. You code works well if you use rev_word.copy() instead of rev_word in loop. You're welcome...
21st Jul 2022, 4:50 PM
Jayakrishna 🇮🇳
+ 3
Solved it! word = input() rev_word = word[::-1] rev_word = list(rev_word) out_word = [] for i in rev_word: if i.isalpha() or i.isspace(): out_word.append(i) out_word= "".join(out_word) print(out_word)
21st Jul 2022, 5:52 PM
Umar Muhammad
Umar Muhammad - avatar
+ 2
Jayakrishna🇮🇳 Thank you so much
21st Jul 2022, 4:41 PM
Umar Muhammad
Umar Muhammad - avatar