Format Checker

Is the Phone Number Formatted Correctly?

Challenge Difficulty: Medium | Estimated completion time: ~15 minutes

Create a function that accepts a string and returns true if it’s in the format of a proper phone number and false if it’s not. Assume any number between 0-9 (in the appropriate spots) will produce a valid phone number.

This is what a valid phone number looks like:

(123) 456-7890

Examples

isValidPhoneNumber("(123) 456-7890")
output = True
 
isValidPhoneNumber("1111)555 2345")
output = False
 
isValidPhoneNumber("098) 123 4567")
output = False

Notes

Don’t forget the space after the closing parenthesis.

Solution

Python

import re def is_valid_phone_number(phone: str) -> bool: """Check if phone number is properly formatted. Args: phone: Phone number string Returns: True if format is (###) <a href="../../../../tags/-" class="tag-link">-</a>, False otherwise """ pattern = r"^\(\d{3}\) \d{3}-\d{4}$" return bool(re.match(pattern, phone)) if __name__ == "__main__": print(is_valid_phone_number("(123) 456-7890")) # True print(is_valid_phone_number("1111)555 2345")) # False print(is_valid_phone_number("098) 123 4567")) # False

Output