It is 3-4 rounds of LeetCode, which is somewhat outside the norm for a DevOps/cloud engineer. Furthermore, companies that offer the same pay do not make you do LeetCode.

You have a hierarchy of directories and some files in some of those directories: /root/devops/dir1/file1.txt, file2.txt, ... /root/devops/dir2/file3.txt, file4, ... /root/devops/file6.in, file7.out, ... ...

Some of these files contain IP addresses inside the text. An IP address is a string of form x.x.x.x where each x is a number from 0 to 255 (inclusive).

For example, say we have file1.txt that looks like this: hello world 127.0.0.1 this is some example 128.99.107.55 file with some correct and incorrect 128.128.4.11 ip 0.11.1115.78 addresses This file contains only 3 IP addresses, namely 127.0.0.1, 128.99.107.55, and 128.128.4.11, since 0.11.1115.78 is not a valid IP address.

Your task is to find all distinct IP addresses from all the files in the /root/devops/ directory and print them in lexicographical order.

Example For the following /root/devops/ directory:

/root/devops/dir1/file1.txt hello world 127.0.0.1 this is some example 128.99.107.55 file with some correct and incorrect 128.128.4.11 ip 0.11.1115.78 addressesaddresses

/root/devops/dir1/file2.txt hello from 74.0.65.76 and 8.dd.99.88.907 good this is some example 306.5.76.35 file with some correct and incorrect 15.128.4.65 ip addresses 0.0.0.0

/root/devops/dir2/file3.txt 127.65.64.1 127.0.64.1 127.0.0.1 exaMple 128.57.107.76 128.57.907.70 file with some correct and incorrect 67.128.4.11 ip addresses 7.7.7.8

/root/devops/dir2/file4.txt hello world 127.98.0.1 this is some example 128.96.107.55 file with some correct and incorrect 128.68.4.11 ip addresses

/root/devops/f.inp hello world 127.0.49.1 this is some example 128.99.58.55 8.88.888.88 77.255.255.254 7.7.257.25 file with some correct and incorrect 26.56.4.23 ip addresses

the output should be: 0.0.0.0 127.0.0.1 127.0.49.1 127.0.64.1 127.65.64.1 127.98.0.1 128.128.4.11 128.57.107.76 128.68.4.11 128.96.107.55 128.99.107.55 128.99.58.55 15.128.4.65 26.56.4.23 67.128.4.11 7.7.7.8 74.0.65.76 77.255.255.254 [execution time limit]