# Validating Credit Card Numbers in Python HackerRank Solution

#### ByBrokenprogrammers

Dec 10, 2022

Hello Programmers, In this post, you will know how to solve the Validating Credit Card Numbers in Python HackerRank Solution. This problem is a part of the HackerRank Python Programming Series.

One more thing to add, don’t directly look for the solutions, first try to solve the problems of Hackerrank by yourself. If you find any difficulty after trying several times, then you can look for solutions.

## Validating Credit Card Numbers in Python Hacker Rank Solution

### Problem

You and Fredrick are good friends. Yesterday, Fredrick received N credit cards from ABCD Bank. He wants to verify whether his credit card numbers are valid or not. You happen to be great at regex so he is asking for your help!A valid credit card from ABCD Bank has the following characteristics:  ► It must start with a 4, 5 or 6.
► It must contain exactly 16 digits.
► It must only consist of digits (0-9).
► It may have digits in groups of 4, separated by one hyphen “-“.
► It must NOT use any other separator like ‘ ‘ , ‘_’, etc.
► It must NOT have 4 or more consecutive repeated digits.

#### Example :

Valid Credit Card Numbers

```4253625879615786
4424424424442444
5122-2368-7954-3214
```

Invalid Credit Card Numbers

```42536258796157867       #17 digits in card number → Invalid
4424444424442444        #Consecutive digits are repeating 4 or more times → Invalid
5122-2368-7954 - 3214   #Separators other than '-' are used → Invalid
44244x4424442444        #Contains non digit characters → Invalid
0525362587961578        #Doesn't start with 4, 5 or 6 → Invalid
```

#### Input Format :

The first line of input contains an integer N.
The next N lines contain credit card numbers

• 0 < N < 100

#### Output Format :

Print ‘Valid’ if the credit card number is valid. Otherwise, print ‘Invalid’. Do not print the quotes.

#### Sample Input :

```6
4123456789123456
5123-4567-8912-3456
61234-567-8912-3456
4123356789123456
5133-3367-8912-3456
5123 - 3567 - 8912 - 3456
```

```Valid
Valid
Invalid
Valid
Invalid
Invalid
```

#### Explanation :

4123456789123456 : Valid
5123-4567-8912-3456 : Valid
61234-576-8912-3456 : Invalid, because the card number is not divided into equal groups of 4.
4123356789123456 : Valid
5133-3367-8912-3456 : Invalid, consecutive digits 3333 is repeating 4 times.
5123 – 4567 – 8912 – 3456 : Invalid, because space ‘  ‘ and `-` are used as separators.

### Validating Credit Card Numbers in Python HackerRank Solutions

```import re
for i in range(int(input())):
N = input().strip()
if N.isalnum() and len(N) == 10:
if bool(re.search(r'(.*[A-Z]){2,}',N)) and bool(re.search(r'(.*[0-9]){3,}',N)):
if re.search(r'.*(.).*\1+.*',N):
print('Invalid')
else:
print('Valid')
else:
print('Invalid')
else:
print('Invalid')```

Disclaimer: The above Problem (Validating Credit Card Numbers in Python) is generated by Hackerrank but the Solution is Provided by BrokenProgrammers. This tutorial is only for Educational and Learning purposes.