How can I loop through a string and print certain items?

Question

lst = \'AB[CD]EF[GH]\'

Output: [\'A\',\'B\',\'CD\',\'E\',\'F\',\'GH\']

This is what I\'ve tried but it\'s not working...

while         


        

Answer 1

You can't use

lst += multi

because you can't concatenate a string with a list.

Moreover, your code enters an infinite loop, because you aren't updating the curr_char variable inside the inner loop, so the condition will always be True.

Also, you are not handling the case when curr_char != '['. And more errors there are.

You can use this code which fixes the above errors while using the same basic logic as your code:

index = 0
multi = ""
res = []
my_str = 'AB[CD]EF[GH]'

while (index < len(my_str)):
    curr_char = my_str[index]
    if curr_char == '[':
        multi += curr_char
        while curr_char != ']':
            index += 1
            curr_char = my_str[index]
            multi += curr_char
        res.append(multi)
        multi = ""
    else:
        res.append(curr_char)
    index += 1

print(res)

Output:

['A', 'B', '[CD]', 'E', 'F', '[GH]']