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exercises/luhn/introduction.md

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+# Introduction
+
+At the Global Verification Authority, you've just been entrusted with a critical assignment.
+Across the city, from online purchases to secure logins, countless operations rely on the accuracy of numerical identifiers like credit card numbers, bank account numbers, transaction codes, and tracking IDs.
+The Luhn algorithm is a simple checksum formula used to ensure these numbers are valid and error-free.
+
+A batch of identifiers has just arrived on your desk.
+All of them must pass the Luhn test to ensure they're legitimate.
+If any fail, they'll be flagged as invalid, preventing errors or fraud, such as incorrect transactions or unauthorized access.
+
+Can you ensure this is done right? The integrity of many services depends on you.