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Regular
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Regular
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Regular Expression
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\b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b34[0-9]{13}\b|\b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b37[0-9]{13}\b
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Input 1
1
New
American Express Requirements: American Express cards start with the number 34 or 37 and have 15 digits. Pattern is 4-6-5 when having spaces or dashes. Pattern Parts: Starts with number 34 and 15 length: 1) \b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b34[0-9]{13}\b Starts with number 37 and 15 length: 2) \b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b37[0-9]{13}\b Combining 1-2 to form one pattern: \b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b34[0-9]{13}\b|\b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b37[0-9]{13}\b Test Cases: Positive (Should fire): 15 length, no space, start with 34 342312341234112 15 length, dashes, start with 34 3423-123456-12345 15 length, spaces, start with 34 3423 123456 12345 15 length, no space, start with 37 372112341234123 15 length, dashes, start with 37 3721-123456-12345 15 length, spaces, start with 37 3721 123456 12345 Embedded in sentence with space: 15 length, no space, start with 34 Here is the cc: 342312341234112 15 length, dashes, start with 34 Here is the cc: 3423-123456-12345 15 length, spaces, start with 34 Here is the cc: 3423 123456 12345 15 length, no space, start with 37 Here is the cc: 372112341234123 15 length, dashes, start with 37 Here is the cc: 3721-123456-12345 15 length, spaces, start with 37 Here is the cc: 3721 123456 12345 15 length, no space, start with 34 Credit Card#:342312341234112 15 length, dashes, start with 34 Credit Card#:3423-123456-12345 15 length, spaces, start with 34 Credit Card#:3423 123456 12345 15 length, no space, start with 37 Credit Card#:372112341234123 15 length, dashes, start with 37 Credit Card#:3721-123456-12345 15 length, spaces, start with 37 Credit Card#:3721 123456 12345 Negative (Should Not Fire): 15 length, no space, not start with 34 352312341234112 15 length, dashes, not start with 34 3523-123456-12345 15 length, spaces, not start with 34 3523 123456 12345 15 length, no space, not start with 37 362112341234123 15 length, dashes, not start with 37 3621-123456-12345 15 length, spaces, not start with 37 3621 123456 12345 15 length, no space, start with 34, embedded Credit Card Number342312341234112 15 length, dashes, start with 34, malformed 3423-1234-1234-112 15 length num matching pattern but embedded User ID: 000000342312341234112000000