Complete Course Available at: https://github.com/Ebad8931/PythonWorkshop Functional Programming Problem is solved in this Presentation by designing a solution using Top-Down approach and implementing the solution using Bottom-Up approach. Problem is available at: https://www.101computing.net/is-my-credit-card-valid/

1. Is my credit card valid?
In this challenge we will use the Luhn Algorithm to
check if a debit card or credit card number is
a valid card number.
This method is used every time you scan or enter
your credit card number (e.g. when paying online) to
check if your card number is a valid credit card
number.
This method can be used to quickly detect credit card numbers that have been
mistyped or to detect when someone is trying to enter a fake/made up credit card
number. Note that it’s not 100% efficient, so is only used a as a pre-check to deter
some invalid card numbers. If this first test passes, other more robust checks will
be performed for the online transaction to be approved.
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2. The Luhn
Algorithm
The Luhn Algorithm
consists of four key steps.
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3. Exercise: Writing Functions
a) Write a function def convert_to_list(credit_card_number) that converts a
string of numbers to a list of numbers (use either map function or list comprehensions)
b) Write a function def luhn_double_digit(digit) that performs doubling of a digit
as per the Luhn Algorithm
c) Write a function def luhn_double(digits_list) that performs the function in (b)
on all the elements of an integer list
d) Write a function def check_credit_card(checksum) that decides whether a
credit/debit card is valid based on the value of the checksum
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4. convert_to_list
luhn_double_digit
check_credit_cardluhn_double
is_my_credit_card_valid
Input Credit
Card number
Output Valid or
Invalid
sum
Exercise: Complete Function
Define a function def is_my_credit_card_valid(credit_card) that calls all the
functions defined in the previous section and outputs True or False depending on if the user’s
credit/debit card is valid or not.
Problem Solving by Bottom-up Approach
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5. Testing our Function
Valid Invalid
Valid Invalid
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6. Thank You!
Problem taken from Python101 challenges
Link to Problem: https://www.101computing.net/is-my-credit-card-valid/
Source code of solution to this Problem will be posted on Github
My Github Link: https://github.com/Ebad8931
Questions?
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