<p>Given a text file <code>file.txt</code> that contains a list of phone numbers (one per line), write a one-liner bash script to print all valid phone numbers.</p> <p>You may assume that a valid phone number must appear in one of the following two formats: (xxx) xxx-xxxx or xxx-xxx-xxxx. (x means a digit)</p> <p>You may also assume each line in the text file must not contain leading or trailing white spaces.</p> <p><strong>Example:</strong></p> <p>Assume that <code>file.txt</code> has the following content:</p> <pre> 987-123-4567 123 456 7890 (123) 456-7890 </pre> <p>Your script should output the following valid phone numbers:</p> <pre> 987-123-4567 (123) 456-7890 </pre>