Why does this code show error

Question

Reversing a string
https://code.sololearn.com/c6TwUA1h5h1M/?ref=app

Answer 1

reverse is to List
you need

s = input()
print(s[::-1])

Answer 2

String could be treated as a list, IF YOU TURN IT TO A LIST:

s = input()
print(s) # output: ABC
s = list(s) # s is now a list of char
s.reverse() # reverse() modify the list in place, no return value (None)
print(s) # output ['C','B','A']
s = ''.join(s) # turn the list of char to a string
print(s) # output CBA

Definitively, it's shorter (and more elegant/pythonistic) to do s[::-1] to reverse a string ^^

String could be compared to special imutable list of char (a tuple of char, in fact), so operation on its elements (modify the list in place) cannot work: that's why string could be treated as list, but wth some limitation ;)

On the other hand, reversed() built-in function don't modify the list in place but return a new one:

s = input() # ABC
print(reverse(s)) # output <reversed object at ...>
print(''.join(reversed(s)) # output 'BCA'

... well, shorter, but not as much as a s[::-1] :P

Answer 3

Thanks

Answer 4

String can be treated as a list right

Answer 5

Not exactly. String can be treated as a list but a string object differs from a list

Answer 6

Alen Antony
You can use SORTED function.

s=input()
print(sorted(s, reverse = True))

Suppose that input is "hello"
Output would be ["o","l","l","e","h"]
But you want it to be joined together, so use JOIN, in the beginning of line.

print("".join(sorted(s, reverse = True)))

You can also use print(s[::-1]), if you know about slicing and stuff.