Financial-Credit-card-number-validation
Financial:Credit card number validation.
Credit card numbers follows 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
6 for Discover cards
In 1954, Habs Luhn of IBM proposed an algorithm for validating credit card numbers. The algorithm is useful to determine whether a card number is entered correctly or whether a credit card is scanned correctly by a scanner. Credit card numbers are generated following this validity check, commonly known as the Luhn check or Mod 10 check, which is described as follows ( for illustration, consider the card number 4388576018402626):
1.Double every second digit from right to left. If double of a digit results in a two-digit number, add up the two digits to get a single digit number.
2.Now add all single-digit number from the step above (Step 1 ).
4 + 4 + 8 + 2 + 3 + 1 + 7 + 8 = 37
3.Add all digits in the odd places from right to left in the card number.
a.6 + 6 + 0 + 8 + 0 + 7 + 8 + 3 = 38
4.Sum the results from the above two step ( Step 2 and Step 3).
37 + 38 = 75
5.If the result from the above step ( step 4 ) is divisible by 10, the card is valid; otherwise, the card is invalid. For example, the card number 4388576018402626 is invalid,but the card number 4388576018410707 is valid.
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Design and Implement the above algorithm in Java Recursively. Your algorithm should prompt the user to enter a credit card number as a long integer. Display whether the number is a valid or invalid credit card number. Design your program to use the following methods: These methods should be done recursively…
//Return if the card number is valid
Public static Boolean isValid(long number)
//Get the result from step 2
Public static int sumOfDoubleEvenPlace( long number )
//Return this number it is a single digit, otherwise, return the sum of the two //digits
Public static intgetDigit( int number )
//Return sum of sumOfOddPlace( long number )
Public static int sumOfOddPlace( long number )
//Return the number of digits in digit
Public static int getSize( long number )
//Return the first k number of digits from the number. If the number of digits in number is less than k, return number
Public static long getPrefix( long number, int k )
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Here are some runs of the program
Enter a credit card number as a long integer
4388576018410707
4388576018410707 is a valid credit card number.
Enter a credit card number as a long integer
4388576018402626
4388576018402626is a valid credit card number.