193_valid_phone_number.sh

# Read from the file file.txt and output all valid phone numbers to stdout.
grep -P "^\([0-9]{3}\) [0-9]{3}-[0-9]{4}$|^[0-9]{3}-[0-9]{3}-[0-9]{4}$" file.txt

# This is my personal record of solving Leetcode Problems. 
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# Copyright (C) 2020-2022  mengxinayan

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