Question

I got this code:

myString = 'blabla123_01_version6688_01_01Long_stringWithNumbers'
versionSplit = re.findall(r'-?\d+|[a-zA-Z!@#$%^&*()_+.,<>{}]+|\W+?', myString)

for i in reversed(versionSplit):
    id = versionSplit.index(i)
    if i.isdigit():
        digit = '%0'+str(len(i))+'d'
        i = int(i) + 1
        i = digit % i
        versionSplit[id]=str(i)
        break

final = ''
myString = final.join(versionSplit)
print myString

Which suppose to increase ONLY the last digit from the string given. But if you run that code you will see that if there is the same digit in the string as the last one it will increase it one after the other if you keep running the script. Can anyone help me find out why?

Thank you in advance for any help

Answer 1

The issue is the use of the list.index() function on line 5. This returns the index of the first occurrence of a value in a list, from left to right, but the code is iterating over the reversed list (right to left). There are lots of ways to straighten this out, but here’s one that makes the fewest changes to your existing code: Iterate over indices in reverse (avoids reversing the list).

for idx in range(len(versionSplit)-1, -1, -1):
    i = versionSplit[idx]
    if chunk.isdigit():
        digit = '%0'+str(len(i))+'d'
        i = int(i) + 1
        i = digit % i
        versionSplit[idx]=str(i)
        break