# 193. Valid Phone Numbers

Given a text file file.txt that contains a list of phone numbers (one per line),
write a one-liner bash script to print all valid phone numbers.

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)

You may also assume each line in the text file must not contain leading or trailing white spaces.

## Example:

Assume that file.txt has the following content:

```
987-123-4567
123 456 7890
(123) 456-7890
```

Your script should output the following valid phone numbers:

```
987-123-4567
(123) 456-7890
```