challenges.yaml

---
# slug: name of the challenge (required)
# description: describe teh challenge (required)
# example: solution for the challenge (required)
# expected_output:
#   lines: lines returned from the command, as an array (required)
#   order: whether or not order matters (optional, default is true)
#   re_sub: regex substitution on the output lines (optional)
#   regex: lines are regular expressions (optional)
#   tests: tests to run after the command completes
#   version: if the challenge is modified this number should be bumped
#            refresh the cache.
#   author: Add a field for contributions.
########## START BEGINNER

  - slug: hello_world
    version: 1
    author: cmdchallenge
    description: |
      Print "hello world".
      Hint: There are many ways to print text on
      the command line, one way is with the 'echo'
      command.

      Try it below and good luck!
    example: echo 'hello world'
    expected_output:
      lines:
        - 'hello world'
  - slug: current_working_directory
    version: 1
    author: cmdchallenge
    description: |
      Print the current working directory.
    example: pwd
    expected_output:
      lines:
        - '/var/challenges/current_working_directory'
  - slug: list_files
    version: 1
    author: cmdchallenge
    description: |
      List all of the files in the current
      directory, one file per line.
    example: ls
    expected_output:
      lines:
        - 'README'
  - slug: print_file_contents
    version: 1
    author: cmdchallenge
    description: |
      There is a file named "access.log" in the
      current directory. Print the contents.
    example: cat access.log
    expected_output:
      lines:
        - 163.56.115.58 - - [09/Jan/2017:22:29:57 +0100] "GET /posts/2/display HTTP/1.0" 200 3240
        - 75.113.188.234 - - [09/Jan/2017:22:30:43 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 1116
        - 69.16.40.148 - - [09/Jan/2017:22:34:33 +0100] "GET /pages/create HTTP/1.0" 500 3471
        - 225.219.54.140 - - [09/Jan/2017:22:35:30 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 500 2477
        - 207.243.19.2 - - [09/Jan/2017:22:38:03 +0100] "GET /bar/create HTTP/1.0" 200 1116
        - 199.37.62.156 - - [09/Jan/2017:22:42:18 +0100] "GET /posts/1/display HTTP/1.0" 200 2477
        - 55.74.240.123 - - [09/Jan/2017:22:44:25 +0100] "POST /posts/1/display HTTP/1.0" 200 3471
        - 251.111.109.143 - - [09/Jan/2017:22:49:02 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 2477
        - 101.163.230.250 - - [09/Jan/2017:22:52:31 +0100] "DELETE /posts/2/display HTTP/1.0" 404 2477
        - 200.19.168.148 - - [09/Jan/2017:22:57:11 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 3471
  - slug: last_lines
    version: 1
    author: cmdchallenge
    disp_title: Last lines in a file.
    description: |
      Print the last 5 lines of "access.log".
    example: tail -n 5 access.log
    expected_output:
      lines:
        - 199.37.62.156 - - [09/Jan/2017:22:42:18 +0100] "GET /posts/1/display HTTP/1.0" 200 2477
        - 55.74.240.123 - - [09/Jan/2017:22:44:25 +0100] "POST /posts/1/display HTTP/1.0" 200 3471
        - 251.111.109.143 - - [09/Jan/2017:22:49:02 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 2477
        - 101.163.230.250 - - [09/Jan/2017:22:52:31 +0100] "DELETE /posts/2/display HTTP/1.0" 404 2477
        - 200.19.168.148 - - [09/Jan/2017:22:57:11 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 3471
  - slug: find_string_in_a_file
    version: 1
    author: cmdchallenge
    description: |
      There is a file named "access.log" in the
      current working directory. Print all lines
      in this file that contains the string "GET".
    example: grep 'GET' access.log
    expected_output:
      lines:
        - 163.56.115.58 - - [09/Jan/2017:22:29:57 +0100] "GET /posts/2/display HTTP/1.0" 200 3240
        - 75.113.188.234 - - [09/Jan/2017:22:30:43 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 1116
        - 69.16.40.148 - - [09/Jan/2017:22:34:33 +0100] "GET /pages/create HTTP/1.0" 500 3471
        - 225.219.54.140 - - [09/Jan/2017:22:35:30 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 500 2477
        - 207.243.19.2 - - [09/Jan/2017:22:38:03 +0100] "GET /bar/create HTTP/1.0" 200 1116
        - 199.37.62.156 - - [09/Jan/2017:22:42:18 +0100] "GET /posts/1/display HTTP/1.0" 200 2477
        - 251.111.109.143 - - [09/Jan/2017:22:49:02 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 2477
        - 200.19.168.148 - - [09/Jan/2017:22:57:11 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 3471
  - slug: find_tabs_in_a_file
    version: 1
    author: cmdchallenge
    description: How many lines contain a tab in the file README
    example: grep -P '\t' file-with-tabs.txt | wc -l
    expected_output:
      lines:
        - 3
  - slug: search_for_files_containing_string
    version: 1
    author: cmdchallenge
    description: |
      Print all files, one per line (not the path, just the file)
      that contain the string "500".
    example: grep -l 500 *
    expected_output:
      order: false
      lines:
        - README
        - access.log
        - access.log.1
  - slug: search_for_files_by_extension
    version: 1
    author: cmdchallenge
    description: |
      Print the relative file paths, one path
      per line for all filenames that start with
      "access.log" in the current directory.

    example: find . -name 'access.log*'
    expected_output:
      order: false
      re_sub: ['^\./', '']
      lines:
        - 'access.log'
        - 'access.log.1'
        - 'access.log.2'
  - slug: search_for_string_in_files_recursive
    version: 1
    author: cmdchallenge
    description: |
      Print all matching lines (without the filename
      or the file path) in all files under the current
      directory that start with "access.log" that
      contain the string "500". Note that there are no
      files named "access.log" in the current directory,
      you will need to search recursively.
    example: grep -h 500 **/access.log*
    expected_output:
      order: false
      lines:
        - 69.16.40.148 - - [09/Jan/2017:22:34:33 +0100] "GET /pages/create HTTP/1.0" 500 3471
        - 225.219.54.140 - - [09/Jan/2017:22:35:30 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 500 2477
        - 2.71.250.27 - - [09/Jan/2017:22:41:26 +0100] "GET /pages/create HTTP/1.0" 500 2477
  - slug: extract_ip_addresses
    version: 1
    author: cmdchallenge
    description: |
      Extract all IP addreses from files
      that start with "access.log" printing one
      IP address per line.
    example: grep -Pho '^\d+\.\d+\.\d+\.\d+' **/access.log*
    expected_output:
      re_sub: ['^[\w/.]*?:', '']
      order: false
      lines:
        - 163.56.115.58
        - 75.113.188.234
        - 69.16.40.148
        - 225.219.54.140
        - 207.243.19.2
        - 199.37.62.156
        - 55.74.240.123
        - 251.111.109.143
        - 101.163.230.250
        - 200.19.168.148
        - 108.68.174.15
        - 17.2.20.139
        - 28.151.137.59
        - 199.150.241.179
        - 2.71.250.27
        - 17.137.186.194
        - 151.84.119.34
        - 4.180.204.195
        - 9.230.96.54
        - 157.143.233.21
  - slug: delete_files
    version: 1
    author: cmdchallenge
    description: |
      Delete all of the files in this challenge
      directory including all subdirectories and
      their contents.
    tests:
      - test: '[[ $(find .) == "." ]]'
        msg: Test failed, files or directories remain.
    example: find . -delete
  - slug: count_files
    version: 1
    author: cmdchallenge
    description: |
      Count the number of files in the current
      working directory. Print the number of
      files as a single integer.
    example: ls | wc -l
    expected_output:
      re_sub: ['^\s+', '']
      lines:
        - '2'
  - slug: simple_sort
    version: 1
    author: cmdchallenge
    disp_title: Sort lines in a file.
    description: |
      Print the contents of access.log
      sorted.
    example: sort access.log
    expected_output:
      lines:
        - 101.163.230.250 - - [09/Jan/2017:22:52:31 +0100] "DELETE /posts/2/display HTTP/1.0" 404 2477
        - 163.56.115.58 - - [09/Jan/2017:22:29:57 +0100] "GET /posts/2/display HTTP/1.0" 200 3240
        - 199.37.62.156 - - [09/Jan/2017:22:42:18 +0100] "GET /posts/1/display HTTP/1.0" 200 2477
        - 200.19.168.148 - - [09/Jan/2017:22:57:11 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 3471
        - 207.243.19.2 - - [09/Jan/2017:22:38:03 +0100] "GET /bar/create HTTP/1.0" 200 1116
        - 225.219.54.140 - - [09/Jan/2017:22:35:30 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 500 2477
        - 251.111.109.143 - - [09/Jan/2017:22:49:02 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 2477
        - 55.74.240.123 - - [09/Jan/2017:22:44:25 +0100] "POST /posts/1/display HTTP/1.0" 200 3471
        - 69.16.40.148 - - [09/Jan/2017:22:34:33 +0100] "GET /pages/create HTTP/1.0" 500 3471
        - 75.113.188.234 - - [09/Jan/2017:22:30:43 +0100] "GET /posts/foo?appID=xxxx HTTP/1.0" 200 1116
  - slug: count_string_in_line
    version: 1
    author: cmdchallenge
    disp_title: Count Matching Lines.
    description: |
      Print the number of lines
      in access.log that contain the string
      "GET".
    example: grep -c "GET" access.log
    expected_output:
      re_sub: ['^\s+', '']
      lines:
        - '8'
  - slug: split_on_a_char
    version: 1
    author: cmdchallenge
    disp_title: Split on a single character.
    description: |
      The file split-me.txt contains a list of
      numbers separated by a ';' character.
      Split the numbers on the ';' character,
      one number per line.
    example: tr ';' '\n' < split-me.txt
    expected_output:
      lines: [1,2,3,4,5,6,7,8,9,10]
  - slug: print_number_sequence
    version: 1
    author: cmdchallenge
    disp_title: Generate a number sequence.
    description: |
      Print the numbers 1 to 100 separated
      by spaces.
    example: echo $(seq 1 100)
    expected_output:
      lines:
        - 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
  - slug: remove_files_with_a_dash
    version: 1
    author: cmdchallenge
    disp_title: Remove files that start with a dash
    description: |
      There are some files in this directory that
      start with a dash in the filename.
      Remove those files.
    example: rm ./-*
    tests:
      - test: '[[ $(find . -type f | wc -l) == 2 ]]'
        msg: Test failed, expecting 2 files.
      - test: '[[ $(find . -name "-*" | wc -l) == 0 ]]'
        msg: Test failed, files with dashes exist
  - slug: remove_files_with_extension
    version: 1
    author: cmdchallenge
    disp_title: Remove files with extension.
    description: |
      There are files in this challenge with
      different file extensions.
      Remove all files with the .doc extension
      recursively in the current working directory.
    example: rm **/*.doc
    tests:
      - test: '[[ $(find . -type f | wc -l) == 5 ]]'
        msg: Test failed, expecting 5 files.
      - test: '[[ $(find . -name "*.doc" | wc -l) == 0 ]]'
        msg: Test failed, expecting 0 files with a .doc extension.
  - slug: remove_files_without_extension
    version: 1
    author: bryfry
    disp_title: Remove files without extension.
    description: |
      There are files in this challenge with
      different file extensions.
      Remove all files without the .txt and .exe extensions
      recursively in the current working directory.
    example: find . -type f -regextype posix-extended ! -regex ".*(\.txt|\.exe)$" -exec rm {} +
    tests:
      - test: '[[ $(find . -type f | wc -l) == 4 ]]'
        msg: Test failed, expecting 4 files.
      - test: '[[ $(find . -name "*.txt" | wc -l) == 3 ]]'
        msg: Test failed, expecting 3 files with a .txt extension.
      - test: '[[ $(find . -name "*.exe" | wc -l) == 1 ]]'
        msg: Test failed, expecting 1 files with a .exe extension.

########## END BEGINNER

########### START INTERMEDIATE
  - slug: replace_text_in_files
    version: 1
    author: cmdchallenge
    disp_title: Replace text in files
    example: sed -i 's/challenges are difficult//g' **/*.txt
    description: |
      This challenge has text files (with a .txt extension)
      that contain the phrase "challenges are difficult".
      Delete this phrase recursively from all text files.
      Note that some files are in subdirectories so you will
      need to search for them.
    tests:
      - test: '[[ $(find . -name "*.txt" | wc -l) == 3 ]]'
        msg: Test failed, expecting 3 text files
      - test: '[[ $(find . -name "*.txt" -print0 | xargs -0 -n1 grep "challenges are difficult") == "" ]]'
        msg: Test failed, found the string "challenges are difficult"
      - test: 'grep -q "challenges are difficult" README'
        msg: Test failed, files without .txt extension must remain unmodified
  - slug: sum_all_numbers
    version: 1
    author: cmdchallenge
    disp_title: Sum numbers in a file.
    example: paste -sd+ sum-me.txt  | bc
    description: |
      The file sum-me.txt have a list of numbers,
      one per line. Print the sum of these numbers.
    expected_output:
      lines:
        - 42
  - slug: just_the_files
    version: 1
    author: cmdchallenge
    disp_title: Print only the filenames
    description: |
      Print all files in the current directory
      recursively without the leading directory path.
    example: find -type f -printf '%f\n'
    expected_output:
      order: false
      lines:
        - animi.doc
        - corporis.xls
        - odit.doc
        - beatae.flac
        - error.doc
        - libero.xls
        - necessitatibus.doc
        - README
        - totam
  - slug: remove_extensions_from_files
    version: 1
    author: cmdchallenge
    disp_title: Remove file extensions.
    description: |
      Remove the extension from all files in
      the current directory recursively.
    example: for f in $(find . -type f -name "*.*"); do mv "$f" "${f%.*}"; done
    tests:
      - test: '[[ $(find . -type f -name "*.*") == "" ]]'
        msg: Test failed, there are still files with extensions in the current directory.
  - slug: replace_spaces_in_filenames
    version: 1
    author: cmdchallenge
    disp_title: Replace spaces in file names.
    description: |
      The files in this challenge contain spaces.
      List all of the files (filenames only) in the
      current directory but replace all spaces with
      a '.' character.
    example: ls | tr ' ' '.'
    expected_output:
      order: false
      lines: ['Adam.Simpson', 'Alexis.Stein', 'Allison.Brown', 'Amy.Anderson', 'Angel.Saunders',
        'Brad.Michael', 'Briana.Wilson', 'Carrie.Alexander', 'Christine.Valdez', 'Christopher.Miller',
        'Claudia.Mccormick', 'Corey.Bird', 'Courtney.Miller', 'Crystal.Dunn', 'Crystal.Valdez',
        'Erica.Richardson', 'James.Harper', 'James.Roberts', 'Jared.Hill.DVM', 'John.Nguyen',
        'Jorge.Ross', 'Joseph.Hurst', 'Karen.Ramirez', 'Kevin.Price', 'Kimberly.Parker', 'Lori.Macias',
        'Luke.Mason', 'Lynn.Robinson', 'Mallory.Peterson', 'Marie.Gutierrez', 'Matthew.Romero',
        'Michaela.Hobbs', 'Molly.Stevens', 'Mr..James.Lopez', 'Mr..Shawn.Martin', 'Mrs..Jade.Clark',
        'Olivia.Irwin', 'Parker.Gilbert', 'README', 'Robert.Gregory', 'Robert.Hill', 'Sarah.Hill',
        'Scott.Rice', 'Sheri.Bishop', 'Tamara.Anderson', 'Tammy.Galloway', 'Terri.Young', 'Thomas.Parks',
        'Thomas.Washington', 'Tiffany.Clark', 'Yvonne.Myers']
  - slug: files_starting_with_a_number
    version: 1
    author: cmdchallenge
    disp_title: Print files starting with a number.
    description: |
      There are a mix of files in this directory
      that start with letters and numbers. Print
      the filenames (just the filenames) of all
      files that start with a number recursively
      in the current directory.
    example: find . -type f -name '[[:digit:]]*' -printf '%f\n'
    expected_output:
      order: false
      lines: ['974Michael Bowman', '540Katherine Jones', '436Teresa Owens', '04Carrie Alexander', '778Holly Archer',
              '3maxime.mp3', '682Terri Jones', '511Tammy Welch', '293Linda Bennett', '670James Jacobs', '737Jeffrey Davis',
              '42Robert Hill', '25Brandon Mcdonald', '402Nancy Henson', '78Michelle Spencer', '132Rebecca Rubio',
              '639Charles Ferguson', '335John Joseph', '99blanditiis.avi', '477Thomas Pierce MD', '757Robert Marquez',
              '388Andrew Carter', '48Thomas Allen', '593Brett Martin']
  - slug: print_nth_line
    version: 1
    author: cmdchallenge
    disp_title: Print the nth line.
    description: |
      Print the 25th line of the file faces.txt
    example: sed -n '25p' faces.txt
    expected_output:
      lines: ['¯\_(ツ)_/¯']
  - slug: remove_duplicate_lines
    version: 1
    author: cmdchallenge
    disp_time: Remove duplicate lines without sorting
    description: |
      Print the file faces.txt, but only print the first instance of each
      duplicate line, even if the duplicates don't appear next to each other.
      Note that order matters so don't sort the lines before removing duplicates.
    example: awk '!x[$0]++' faces.txt
    expected_output:
      lines: ['(◕‿◕)', '(^̮^)', 'ʘ‿ʘ', 'ಠ_ಠ', 'ಠ⌣ಠ', 'ಠ‿ಠ', '(ʘ‿ʘ)', '(ಠ_ಠ)', '¯\_(ツ)_/¯',
              '(ಠ⌣ಠ', 'ಠಠ⌣ಠ)', '(ಠ‿ಠ)', '٩◔̯◔۶', 'ヽ༼ຈل͜ຈ༽ﾉ', '♥‿♥', '◔̯◔', '⊙﹏⊙',
              '(¬_¬)', '(；一_一)', '(͡° ͜ʖ ͡°)', '(° ͜ʖ °)', '¯\(°_o)/¯', '( ﾟヮﾟ)', '(︺︹︺)']
  - slug: corrupted_text
    version: 1
    author: cmdchallenge
    disp_title: Removing extra '!' characters from text
    example: perl -pne  's/!(?![ \n])//g;' war_and_peace.txt | perl -pne 's/(?<=[.])!//g' | perl -pne 's/!(?= [a-z])//g'
    description: |
      The following excerpt from War and Peace is saved to
      the file 'war_and_peace.txt':

      She is betraying us! Russia alone must save Europe.
      Our gracious sovereign recognizes his high vocation
      and will be true to it. That is the one thing I have
      faith in! Our good and wonderful sovereign has to
      perform the noblest role on earth, and he is so virtuous
      and noble that God will not forsake him. He will fulfill
      his vocation and crush the hydra of revolution, which
      has become more terrible than ever in the person of this
      murderer and villain!

      The file however has been corrupted, there are random '!'
      marks inserted throughout.  Print the original text.
    expected_output:
      lines:
        - She is betraying us! Russia alone must save Europe.
        - Our gracious sovereign recognizes his high vocation
        - and will be true to it. That is the one thing I have
        - faith in! Our good and wonderful sovereign has to
        - perform the noblest role on earth, and he is so virtuous
        - and noble that God will not forsake him. He will fulfill
        - his vocation and crush the hydra of revolution, which
        - has become more terrible than ever in the person of this
        - murderer and villain!
  - slug: print_common_lines
    version: 1
    author: amboar
    disp_title: Print common lines
    order: false
    example: "comm -12 <(cut -d' ' -f1 access.log.1 | sort) <(cut -d' ' -f1 access.log.2 | sort)"
    description: |
      access.log.1 and access.log.2 are http server logs. Print the IP
      addresses common to both files, one per line.
    expected_output:
      lines:
        - 108.68.174.15
        - 17.137.186.194
        - 2.71.250.27
        - 28.151.137.59
########### END INTERMEDIATE