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id, title, challengeType, dashedName
id title challengeType dashedName
68cae5b538ff798bbd4da006 Challenge 68: Credit Card Masker 29 challenge-68

--description--

Given a string of credit card numbers, return a masked version of it using the following constraints:

  • The string will contain four sets of four digits (0-9), with all sets being separated by a single space, or a single hyphen (-).
  • Replace all numbers, except the last four, with an asterisk (*).
  • Leave the remaining characters unchanged.

For example, given "4012-8888-8888-1881" return "****-****-****-1881".

--hints--

mask("4012-8888-8888-1881") should return "****-****-****-1881".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(mask("4012-8888-8888-1881"), "****-****-****-1881")`)
}})

mask("5105 1051 0510 5100") should return "**** **** **** 5100".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(mask("5105 1051 0510 5100"), "**** **** **** 5100")`)
}})

mask("6011 1111 1111 1117") should return "**** **** **** 1117".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(mask("6011 1111 1111 1117"), "**** **** **** 1117")`)
}})

mask("2223-0000-4845-0010") should return "****-****-****-0010".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(mask("2223-0000-4845-0010"), "****-****-****-0010")`)
}})

--seed--

--seed-contents--

def mask(card):

    return card

--solutions--

def mask(card):
    if '-' in card:
        split = card.split('-')
        return f"****-****-****-{split[3]}"
    else:
        split = card.split(' ')
        return f"**** **** **** {split[3]}"