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+Learning Profile for Assignment #2, And Question #3
+
+Name: Mo Khan
+Student ID: 3431709
+
+1. Problem Statement:
+
+```text
+Credit card numbers follow certain patterns.
+A credit card number must have between 13 and 16 digits.
+It must start with 4 for Visa cards, 5 for Master cards, 37 for American Express cards, and 6 for Discover cards.
+In 1954, Hans Luhn of IBM proposed the following algorithm for validating credit card numbers:
+* a. Double every second digit from right to left (e.g., if number is 3 => 3 * 2 => 6) and add them together.
+* b. If this doubling results in a two-digit number, then add the two digits to get a single-digit number (e.g., if number is 5 => 5 * 2 => 10 => 1+0 => 1).
+
+So, for the credit card number 4388576018402626, doubling all second digits from the right results in
+
+```text
+ (2 * 2 = 4) + (2 * 2 = 4) + (4 * 2 = 8) + (1 * 2 = 2) + (6 * 2 = 12 = 1 + 2 = 3) + (5 * 2 = 10 = 1 + 0 = 1) + (8 * 2 = 16 = 1 + 6 = 7) + (4 * 2 = 8).
+```
+
+This totals to 4 + 4 + 8 + 2 + 3 + 1 + 7 + 8 = 37.
+
+Add all digits in the odd places from right to left.
+The leftmost digit of the credit card number is at index 0;
+
+6 + 6 + 0 + 8 + 0 + 7 + 8 + 3 = 38.
+
+Add results from steps (a) and (b) and see if divisible by 10.
+If it is, then the card number is valid; otherwise invalid.
+
+37 + 38 = 75 is not divisible by 10, so it is an invalid credit card number.
+
+Implement Luhn’s algorithm in a program to determine whether a given credit card number is valid or not.
+You must test if the number of digits in the input is in the valid range (13 to 16), run Luhn’s algorithm to test its validity,
+and if it is valid, print the name of the company that offers that credit card number.
+```
+
+2. Description of the Code:
+3. Errors and Warnings:
+4. Sample Input and Output:
+5. Discussion: