Debug an ISBN Validator - Debug an ISBN Validator

Python
1

Tell us what’s happening:

here is my code, i have a problem with the valid and invalid print out statements while the rest are running just fine .kindly assist

Your code so far

def validate_isbn(isbn, length):
    if len(isbn, length) != length:
        print(f'ISBN-{length} code should be {length} digits long.')
        return
    main_digits = isbn[0:length]
    given_check_digit = isbn[length]
    main_digits_list = [int(digit) for digit in main_digits]
    # Calculate the check digit from other digits
    if length == 10:
        expected_check_digit = calculate_check_digit_10(main_digits_list)
    else:
        expected_check_digit = calculate_check_digit_13(main_digits_list)
    # Check if the given check digit matches with the calculated check digit
    if given_check_digit == expected_check_digit:
        print('Valid ISBN Code.')
    else:
        print('Invalid ISBN Code.')
def calculate_check_digit_10(main_digits_list):
    # Note: You don't have to fully understand the logic in this function.
    digits_sum = 0
    # Multiply each of the first 9 digits by its corresponding weight (10 to 2) and sum up the results
    for index, digit in enumerate(main_digits_list):
        digits_sum += digit * (10 - index)
    # Find the remainder of dividing the sum by 11, then subtract it from 11
    result = 11 - digits_sum % 11
    # The calculation result can range from 1 to 11.
    # If the result is 11, use 0.
    # If the result is 10, use upper case X.
    # Use the value as it is for other numbers.
    if result == 11:
        expected_check_digit = '0'
    elif result == 10:
        expected_check_digit = 'X'
    else:
        expected_check_digit = str(result)
    return expected_check_digit
def calculate_check_digit_13(main_digits_list):
    # Note: You don't have to fully understand the logic in this function.
    digits_sum = 0
    # Multiply each of the first 12 digits by 1 and 3 alternately (starting with 1), and sum up the results
    for index, digit in enumerate(main_digits_list):
        if index % 2 == 0:
            digits_sum += digit * 1
        else:
            digits_sum += digit * 3
    # Find the remainder of dividing the sum by 10, then subtract it from 10
    result = 10 - digits_sum % 10
    # The calculation result can range from 1 to 10.
    # If the result is 10, use 0.
    # Use the value as it is for other numbers.
    if result == 10:
        expected_check_digit = '0'
    else:
        expected_check_digit = str(result)
    return expected_check_digit
#def main():
        #user_input = input('Enter ISBN and length: ')
    values = user_input.split(',')
    #isbn = values[0]
    #length = int(values[1])
    #if length == 10 or length == 13:
    #validate_isbn(isbn, length)
    #else:
    #print('Length should be 10 or 13.')
#main() 

def main():
 try:
    user_input=input('Enter ISBN and length:')
    if not ',' in user_input:
        print('Enter comma-separated values.')
    if not isinstance(user_input,int):
        print('Length must be a number.')
 except:
        print ("Invalid ISBN Code.")
 for ISBNcode in user_input:
    if len(ISBNcode) != 10 or 13:
            print('Length should be 10 or 13.')
            break
    for ISBNcode in user_input:
        if len(ISBNcode)>=13:
            print('ISBN-13 code should be 13 digits long.')
            break
    for ISBNcode in user_input:
        if len(ISBNcode)>=10:
            print('ISBN-10 code should be 10 digits long.')
            break
    for ISBNcode in user_input:
        if ISBNcode != int:
            print("Invalid character was found.")
            break

           
main()

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Challenge Information:

Debug an ISBN Validator - Debug an ISBN Validator

2

What problem do you have?

3

Your code fails this test:

  1. When the user enters an incorrect ISBN code with characters other than numbers, you should see the message Invalid character was found. in the console.

If I test it with an invalid character:

Enter ISBN and length:
15-0051126,10
Length must be a number.
Length should be 10 or 13.

You can start by investigating this line

    if not isinstance(user_input,int):
        print('Length must be a number.')

Why is that if statement triggering?

use print() to find out what user_input is.

4

it was tough but i passed it thanks

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