print string in reverse

[pseudo]

fruit = 'banana'
index = 0
while index < len(fruit):
    letter = fruit[index]
    print(letter, end='')
    index = index + 1

I tried to reverse the string by changing 3rd line to letter = fruit[-index], but it didn't work

[wavic]

>>> s = 'Welcome to the forum!'
>>> s[::-1]
'!murof eht ot emocleW'
>>> 

This is called slicing. The format is [start_index, stop_index, step]. Stop_index is exclusive. In this case, the start and the stop are missing which means we get the whole string. And since the step is negative it counts backward.

[pseudo]

>>> s = 'Welcome to the forum!'
>>> s[::-1]
'!murof eht ot emocleW'
>>> 

This is called slicing. The format is [start_index, stop_index, step]. Stop_index is exclusive. In this case, the start and the stop are missing which means we get the whole string. And since the step is negative it counts backward.

thanks for the reply and the welcome . but slicing is explained after the exercise. so i solved it like this instead.

fruit = 'banana'
index = len(fruit) - 1
while index >= 0:
    letter = fruit[index]
    print(letter, end='')
    index = index - 1

[gruntfutuk]

This would have been simpler if you can't use slicing yet:

fruit = 'banana'
reverse = ''
for letter in fruit:
    reverse = letter + reverse
print(reverse)

We generally avoid directly indexing into lists/strings/etc if we don't need to.

[pseudo]

This would have been simpler if you can't use slicing yet:

fruit = 'banana'
reverse = ''
for letter in fruit:
    reverse = letter + reverse
print(reverse)

We generally avoid directly indexing into lists/strings/etc if we don't need to.

I don't get it. shouldn't that just go through each letter and print the result. why did it do it in reverse?

[buran]

why did it do it in reverse?

because each letter is added at the begining of the result. to see it

fruit = 'banana'
reverse = ''
for letter in fruit:
    reverse = letter + reverse
    print(reverse)