정규표현식 연습문제 풀이

연습문제를 풀고 이를 노트북으로 정리

https://regex101.com/ 활용해보기

#1 All Lessons

Lesson1. An Introduction, and the ABCs

Task	Text
Match	abcdefg
Match	abcde
Match	abc

Answer : abc

Lesson1 1/2. The 123s

Task	Text
Match	abc123xyz
Match	define “123”
Match	var g = var g 123;

Answer : 123

Lesson2. The Dot

Task	Text
Match	cat.
Match	896.
Match	?=+.
Skip	abc1

Answer : .+[^abc1]

Lesson3. Matching specific characters

Task	Text
Match	can
Match	man
Match	fan
Skip	dan
Skip	ran
Skip	pan

Answer : [c

f]an

Lesson4. Excluding specific characters

Task	Text
Match	hog
Match	dog
Skip	bog

Answer : [h

d]og

Lesson5. Character ranges

Task	Text
Match	Ana
Match	Bob
Match	Cpc
Skip	aax
Skip	bby
Skip	ccz

Answer : [A-C].+

Lesson6. Catching some zzz’s

Task	Text
Match	wazzzzzup
Match	wazzzup
Skip	wazup

Answer : ^waz{2,5}up

Lesson7. Mr. Kleene, Mr. Kleene

Task	Text
Match	aaaabcc
Match	aabbbbc
Match	aacc
Skip	a

Answer : abc+

Lesson8. Characters optional

Task	Text
Match	1 file found?
Match	2 files found?
Match	24 files found?
Skip	No files found.

Answer : \d.+

Lesson9. All this whitespace

Task	Text
Match	1. abc
Match	2. abc
Match	3. abc
Skip	4.abc

Answer: [1-3].\s+abc

Lesson10. Starting and ending

Task	Text
Match	Mission: successful
Skip	Last Mission: unsuccessful
Skip	Next Mission: successful upon capture of target

Answer : ^[^Next

Last

].+[^un]successful$

Lesson11. Match Groups

주의점: 제시된 캡쳐그룹만을 따로 잡아내야함

Task	Text
Capture	file_record_transcript.pdf
Capture	file_07241999.pdf
Skip	testfile_fake.pdf.tmp

Capture Groups file_record_transcript file_07241999

Answer : ^(file\w+).pdf

Lesson12. Nested groups

Task	Text
Capture	Jan 1987
Capture	May 1969
Capture	Aug 2011

Capture Groups Jan 1987 1987 May 1969 1969 Aug 2011 2011

Answer : (\w+ (\d+))

문장내에서 위의 두가지 캡쳐그룹을 잡아내는 정규식 : \b([B-Z].+ (19\d+))\b

Lesson13. More group work

Task	Text
Capture	1280x720
Capture	1920x1600
Capture	1024x768

Capture Groups 1280 720 1920 1600 1024 768

Answer : ((\d+)x(\d+))

Lesson14. More group work

Task	Text
Match	I love cats
Match	I love dogs
Skip	I love logs
Skip	I love cogs

Answer : I love (cats

dogs)

Lesson15. Other special characters

Task	Text
Match	The quick brown fox jumps over the lazy dog.
Match	There were 614 instances of students getting 90.0% or above.
Match	The FCC had to censor the network for saying &$#*@!.

Answer : .*

#2 Practice Problems

Problem 1: Matching a decimal numbers

Task	Text
Match	3.14529
Match	-255.34
Match	128
Match	1.9e10
Match	123,340.00
Skip	720p

Answer : .+\d$

Problem 2: Matching phone numbers

Task	Text	Captrue Groups
Capture	415-555-1234	`415`
Capture	650-555-2345	`650`
Capture	(416)555-3456	`416`
Capture	202 555 4567	`202`
Capture	4035555678	`403`
Capture	1 416 555 9292	`416`

Answer : 1?[\s]?(?(\d{3}))?[\s-]?\d{3}[\s-]?\d{4}

Problem 3: Matching emails

Task	Text	Captrue Groups
Capture	tomtom@hogwarts.com	`tom`
Capture	tom.riddle@hogwarts.com	`tom.riddle`
Capture	tom.riddle+regexone@hogwarts.com	`tom.riddle`
Capture	tom@hogwarts.eu.com	`tom`
Capture	potter@hogwarts.com	`potter`
Capture	harry@hogwarts.com	`harry`
Capture	hermione+regexone@hogwarts.com	`hermione`

Answer : ((\w+)[+.]?\w+)

Problem 4: Matching HTML

Task	Text	Captrue Groups
Capture	<a>This is a link</a>	`a`
Capture	<a\ href=’https://regexone.com’>Link</a>	`a`
Capture	<div\ class=’test_style’>Test</div>	`div`
Capture	<div>Hello <span>world</span></div>	`div`

Answer : <(a

div)>?.+\w?<(/a

/div)>

Problem 5: Matching specific filenames

Task	Text	Captrue Groups
Skip	.bash_profile
Skip	workspace.docwork
Capture	img0912.jpg	`img0912` `jpg`
Capture	updated_img0912.png	`updated_img0912` `png`
Skip	documentation.html
Capture	favicon.gif	`favicon` `gif`
Skip	img0912.jpg.tmp
Skip	access.lock

Answer : (\w+).(jpg

png

gif)$

Problem 6: Trimming whitespace from start and end of line

Task	Text	Captrue Groups
Capture	The quick brown fox…	`The quick brown fox...`
Capture	jumps over the lazy dog.	`jumps over the lazy dog.`

Answer : ^\s*(\w.+)$

Problem 7: Extracting information from a log file

Task	Text	Captrue Groups
Skip	W/dalvikvm( 1553): threadid=1: uncaught exception
Skip	E/( 1553): FATAL EXCEPTION: main
Skip	E/( 1553): java.lang.StringIndexOutOfBoundsException
Capture	E/( 1553): at widget.List.makeView(ListView.java:1727)	`makeView` `ListView.java` `1727`
Capture	E/( 1553): at widget.List.fillDown(ListView.java:652)	`fillDown` `ListView.java` `652`
Capture	E/( 1553): at widget.List.fillFrom(ListView.java:709)	`fillFrom` `ListView.java` `709`

Answer : \w.*List.(makeView

fillDown

fillFrom).+(ListView.java).(\w+).

Solution(캡쳐그룹만 잡기) : (\w+)(([\w.]+):(\d+))

( : ‘(‘를 나타냄

Promblem8: Parsing and extracting data from a URL

Task	Text	Captrue Groups
Capture	ftp://file_server.com:21/top_secret/life_changing_plans.pdf	`ftp` `file_server.com` `21`
Capture	https://regexone.com/lesson/introduction#section	`https` `regexone.com`
Capture	file://localhost:4040/zip_file	`file` `localhost` `4040`
Capture	https://s3cur3-server.com:9999/	`https` `s3cur3-server.com` `9999`
Capture	market://search/angry%20birds	`market` `search`

Answer : (\w+)://([\w-.]+).(\d+)?.*