Enter your code here. Read input from STDIN. Print output to STDOUT

import re

N = int(input()) credit_num = [] for _ in range(N): cred = input().strip() # Read each line and strip any extra whitespace credit_num.append(cred) # Append the entire line as a single entry

for n in credit_num: if (re.match(r'^[4-6]', n) and len(re.sub(r'[^0-9]', '', n)) == 16 and re.match(r'^[0-9-]+', n) or re.match(r'^\d{16}$', n)) and not re.search(r'(\d)\1{3,}', re.sub(r'[^0-9]', '', n))): print("Valid") else: print("Invalid")

pattern = r"^(?!.*([0-9])(?:-?\1){3})([456]\d{3})-?(\d{4})-?(\d{4})-?(\d{4})$"

Enter your code here. Read input from STDIN. Print output to STDOUT

def check_no_of_digits(p): digits_list = [i for i in p if i.isdigit()] if len(digits_list) == 16: return True return False def check_starting_digits(q): if q[0]=='4' or q[0]=='5' or q[0]=='6': return True return False def check_digits(r): for i in r: if not i.isdigit(): return False return True def check_hyphens(s): if "-" not in s: return True else: l = s.split("-") for i in l: if len(i)!=4: return False return True def consecutive_check(t): lst = [i for i in t if i.isdigit()] #print(lst) for i in range(len(lst) - 3): # Ensure we check till len(lst) - 4 if lst[i] == lst[i+1] == lst[i+2] == lst[i+3]: return True return False n = int(input()) c = 0 for i in range(n): x = input() y = check_no_of_digits(x) z = check_starting_digits(x) a = check_digits(x) b = check_hyphens(x) c = consecutive_check(x) if y and z and a and not c and b: print("Valid") else: print("Invalid")

Fredrick should verify his ABCD Bank credit card by ensuring it starts with 4, 5, or 6, has exactly 16 digits, only contains numbers (or groups separated by hyphens), and doesn’t have four or more consecutive repeating digits. Regex is a great way to catch mistakes quickly. If he ever faces issues with claims or disputes, he might want to check out PCP Claims for possible solutions.

python3

import re 

check1 = r'(?=(.)(-?\1){3,}.*)' # repeat
validcredit = r'^(4|5|6)[0-9]{3}(-?[0-9]{4}){3}$'

check1 = re.compile(check1)
check2 = re.compile(validcredit)

t = int(input())

for i in range(t):
    num = input()
    if check1.search(num):
        print("Invalid")
    elif check2.match(num):
        print("Valid")
    else:
        print("Invalid")