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  1. Prepare
  2. Python
  3. Regex and Parsing
  4. Validating Credit Card Numbers
  5. Discussions

Validating Credit Card Numbers

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464 Discussions

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  • rejin_gunasekar1
     + 0 comments
    import re
p = r'^[456]\d{3}(-?\d{4}){3}$'
for _ in range(int(input())):
    s  = input()
    if re.match(p, s):
        s = s.replace('-', '')
        if not re.search(r'(.)\1{3}', s):
            print("Valid")
        else:
            print("Invalid")
    else:
        print("Invalid")

  • blaskobenjamin
     + 0 comments
    import re

n = int(input())

pattern = re.compile(r'^[4-6](\d{3})-?(\d{4})-?(\d{4})-?(\d{4})$')
pattern_duplicate = re.compile(r'(\d)\1{3}')

for x in range(n):
    card = input()
    if bool(pattern.match(card)):
        valid_card = re.sub(r'-', "", card)
        if not bool(pattern_duplicate.search(valid_card)):
            print("Valid")
        else:
            print("Invalid")
        
    else:
        print("Invalid")

  • debjyoti_ghosh
     + 0 comments
    import re
# Function to validate credit card numbers
def validate_credit_card(card_number):	
    pattern = r'^[456]\d{3}(-?\d{4}){3}$'    # Regex pattern for a valid card number
# Check if the card matches the pattern and has no consecutive repeated digits
    if re.match(pattern, card_number) and not re.search(r'(\d)\1{3,}', card_number.replace('-', '')):
        return "Valid"
    else:
        return "Invalid"
no_of_cards = int(input())
card_numbers = [input() for _ in range(no_of_cards)]

# Applying the function to each card number
results = [validate_credit_card(card) for card in card_numbers]
for result in results:
    print(result)

  • pnagar303
     + 0 comments

    Test case 3 is failed and i am not getting the problem where is : This is my code:

    import re

    def check(s): #1check if no of digits are 16 or not after removing - if len(s.replace("-",""))==16: for i in s: if i=="-" or i.isdigit(): continue else: return "Invalid"

        pattern=r"[456]\d{3}(-?\d{4}){3}"
    s_new=s.replace('-',"")
    c=1

    #checking repetetion of same digit equal to or more than 4
    for i in range(len(s_new)-1):
        if "-" in s_new:
            match=re.finditer(r"-",s_new)
            index=[x.start() for x in match]
            if index==[3,7,11]:
                pass
            else:
                return "Invalid"

        if s_new[i]==s_new[i+1]:
            c+=1
            if c==4:
                return "Invalid"
            continue
        else:
            c=1
    if c==1:
        if re.match(pattern,s):
            return "Valid"
        else:
            return "Invalid"

else:
    return "Invalid"

    n=int(input()) for _ in range(n): s=input() result=check(s) print(result)

  • huzaifakhan1731
     + 0 comments

    import re

    def is_valid(crd_no):

    pattern = r"^(?!.*(\d)(?:-?\1){3})([4-6]\d{3}(-?\d{4}){3})$"

    return bool(re.match(pattern, crd_no))

    n = int(input())

    crd_no = [input() for _ in range(n)]

    for card in crd_no:

    result = is_valid(card) if result:

    print("Valid")

    lse: print("Invalid")