LeetCode--Valiad Phone Nums

题目

Given a text file file.txt that contains 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.

For example, assume that file.txt has the following content:

solution:

这里写代码片

sed -n -e ‘/(^[0-9]{3}-[0-9]{3}-[0-9]{4}$\|^[(][0-9]\{3\}[)] [0-9]\{3\}-[0-9]\{4\}$)/p’ file.txt