# Learn How to Work with Numbers and Strings by Implementing the Luhn Algorithm - Step 27

### Tell us what’s happening:

Describe your issue in detail here.

``````def verify_card_number(card_number):
sum_of_odd_digits = 0
card_number_reversed = card_number[::-1]
odd_digits = card_number_reversed[::2]

for digit in odd_digits:
sum_of_odd_digits += int(digit)

# User Editable Region

sum_of_even_digits = 0
even_digits = card_number_reversed[1::2]

for digit in even_digits:
if digit >= 10:
print(digit)
digit = int(digit)*2

# User Editable Region

def main():
card_number = '4111-1111-4555-1142'
card_translation = str.maketrans({'-': '', ' ': ''})
translated_card_number = card_number.translate(card_translation)

verify_card_number(translated_card_number)

main()
``````

User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36`

### Challenge Information:

Learn How to Work with Numbers and Strings by Implementing the Luhn Algorithm - Step 27

You appear to have created this post without editing the template. Please edit your post to Tell us what’s happening in your own words.
Learning to describe problems is hard, but it is an important part of learning how to code.
Also, the more you say, the more we can help!

Hi @vsudhakarnaidu31,
Try reset and reattempt.

You have declared the variable `number` in previous task.
Now you are trying to print it. But you want a condition to be checked before printing.

And below is a picture of the steps to guide:

``````for loop:
declaring variable
if condition:
print function
``````

Happy coding

— removed solution screenshot -----

It is great that you solved the challenge, but instead of posting your full working solution, it is best to stay focused on answering the original poster’s question(s) and help guide them with hints and suggestions to solve their own issues with the challenge.

We are trying to cut back on the number of spoiler solutions found on the forum and instead focus on helping other campers with their questions and definitely not posting full working solutions.

Hi. Sorry for that. I didn’t mean to brag. My technical English isn’t sufficient to quickly explain what’s the issue was. I just wanted to help quickly, that’s why dropped a screenshot. That was my first comment on the forum. My apologies for that. Thanks for pointing that out.

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