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About the developer

162 Stars 36 Forks 1.3K Commits 1 Opened issues


This is a project with a collection of coding challenges for those who wants to commit themselves to code at least one hour a day for at least a hundred days.

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Contributors list

# 267,954
20 commits
# 159,822
7 commits


The idea of the project is to commit yourself at least one hour a day to code in any language you want for a hundred days (at least). The regularity is key here, you need to practice a bit everyday, including the weekends. All the challenges present here are medium/hard level. You can (and you should) participate even if you don't have much experience with coding, it will only take a bit longer. Most of the challenges can be solved in three hours or less.

🚩 Rules

  • The main rule is: Code at least an hour every day (don't skip weekends/holidays)
  • Choose a language you wan't to learn or improve
  • Share your progress daily in your social medias
  • Don't copy code from the internet
  • Try to come up with a clean and elegant solution
  • Always write tests (and make them pass)


    day-01 - Convert Age to Days - [Already solved with Go, Go-rschio, Rust, c++, cs, csharp, dart, dart-02, elx, haskell, kts, php, py, py2, ts]
    day-02 - Finding Nemo - [Already solved with Dart-muclemente, Go, Go-rschio, c++, cs, csharp, dart, elx, haskell, kts, php, py, py2]
    day-03 - Barbecue Skewers - [Already solved with Dart-muclemente, Go, c++, cs, csharp, dart, haskell, kts, php, py, py2]
    day-04 - Is Johnny Making Progress? - [Already solved with Go, Swift, c++, csharp, dart, haskell, kts, php, py, py2]
    day-05 - Pair of Socks - [Already solved with Go, Swift, c++, csharp, dart, haskell, kts, py, py2]
    day-06 - Next Prime - [Already solved with Go, Swift, c++, csharp, dart, haskell, kts, py, py2]
    day-07 - Merge Sorted Array - [Already solved with Go, c++, csharp, dart, haskell, kts, py, py2]
    day-08 - Letter Combinations of a Phone Number - [Already solved with c++, csharp, dart, go, kts, py, py2]
    day-09 - Trapping Rain Water - [Already solved with c++, dart, go, kts]
    day-10 - Unique Binary Search Trees - [Already solved with Go, c++, dart, kts]
    day-11 - Restore IP Addresses - [Already solved with Go, c++, dart, kts]
    day-12 - Mountains or Valleys - [Already solved with Go, c++, cs, kts]
    day-13 - Need Help With Your Packing? - [Already solved with Go, c++, cs, kts]
    day-14 - The Karaca's Encryption Algorithm - [Already solved with Go, c++, cs, kts]
    day-15 - Valid Anagram - [Already solved with Go, c++, cs, kts]
    day-16 - Nim Game - [Already solved with Go, c++, csharp, kts]
    day-17 - Prison Break - [Already solved with Go, c++, csharp, kts]
    day-18 - Unique Paths - [Already solved with Go, c++, csharp, kts]
    day-19 - URL Shortener - [Already solved with Go, c++, kts]
    day-20 - API Challenge - [Already solved with Go, c++, kts]
    day-21 - Random Maze Generator - [Already solved with Go, c++]
    day-22 - Marcio Mello's Challenge - [Already solved with Go, c++]
    day-23 - The Dining Philosophers - [Already solved with Go, c++]
    day-24 - The Josephus Problem - [Already solved with Go, c++]
    day-25 - Coin Trouble - [Already solved with Go, c++]
    day-26 - Briefcase Lock - [Already solved with Go, c++]
    day-27 - Task Scheduler - [Already solved with Go, c++]
    day-28 - Word Search - [Already solved with Go, c++]
    day-29 - Traffic Light Checker - [Already solved with Go, c++]
    day-30 - The Maximum Value - [Already solved with Go, c++]
    day-31 - The Time in Words - [Already solved with Go, c++]
    day-32 - Climbing the Leaderboard - [Already solved with Go, c++]
    day-33 - WERTYU - [Already solved with Go, c++]
    day-34 - Primary Arithmetic - [Already solved with Go, c++]
    day-35 - Dog and Gopher - [Already solved with Go, c++]
    day-36 - LCD Display - [Already solved with Go, c++]
    day-37 - Breaking the Records - [Already solved with Go, c++]
    day-38 - Electronics Shop - [Already solved with Go, c++]
    day-39 - Halloween Sale - [Already solved with Go, c++]
    day-40 - Larry's Array - [Already solved with Go, c++]
    day-41 - Sales by Match - [Already solved with Go, c++]
    day-42 - Drawing Book - [Already solved with Go, c++]
    day-43 - Area of a Triangle - [Already solved with Go, c++]
    day-44 - Maximum Edge of a Triangle - [Already solved with Go, c++]
    day-45 - Subtract the swapped bits without temp storage - [Already solved with Go, c++]
    day-46 - Hot Pics of Danny DeVito! - [Already solved with Go, c++]
    day-47 - Zip It! - [Already solved with Go, c++]
    day-48 - Christmas Tree - [Already solved with Go, c++]
    day-49 - Swimming Pool - [Already solved with Go, c++]
    day-50 - Tic Tac Toe - [Already solved with Go, c++]
    day-51 - Asteroid Collision - [Already solved with Go, c++]
    day-52 - Switch on the Gravity - [Already solved with Go, c++]
    day-53 - Javelin Parabolic Throw - [Already solved with Go, c++]
    day-54 - RGB to Hex Color Converter - [Already solved with Go, c++]
    day-55 - Filter Repeating Character Strings - [Already solved with Go, c++]
    day-56 - Convert to Hex - [Already solved with Go, c++]
    day-57 - Magic Sigil Generator - [Already solved with Go, c++]
    day-58 - Create a Dice Roller - [Already solved with Go, c++]
    day-59 - Perfectly balanced - [Already solved with Go, c++]
    day-60 - A Game of Threes - [Already solved with Go, c++]
    day-61 - Write a Web Crawler - [Already solved with Go, c++]
    day-62 - Funny plant - [Already solved with Go, c++]
    day-63 - The rabbit problem - [Already solved with Go, c++]
    day-64 - First Recurring Character - [Already solved with Go, c++]
    day-65 - ISBN Validator - [Already solved with Go, c++]
    day-66 - ISBN Generator - [Already solved with Go, c++]
    day-67 - Color maze - [Already solved with Go, c++]
    day-68 - Clarence the Slow Typist - [Already solved with Go, c++]
    day-69 - Garage Door Opener - [Already solved with Go, c++]
    day-70 - Broken Keyboard - [Already solved with Go, c++]
    day-71 - How long has the light been on? - [Already solved with Go, c++]
    day-72 - L33tspeak Converter - [Already solved with Go, c++]
    day-73 - L33tspeak Translator - [Already solved with Go, c++]
    day-74 - CATTLEMETER - [Already solved with Go, c++]
    day-75 - Minesweeper - [Already solved with Go, c++]
    day-76 - The Cake Thief - [Already solved with Go, c++]
    day-77 - Bot saves princess - [Already solved with Go, c++]
    day-78 - A number without numbers - [Already solved with Go, c++]
    day-79 - Analog Clock - [Already solved with Go, c++]
    day-80 - Make it look like you are working - [Already solved with Go, c++]
    day-81 - Draw the “G” Logo - [Already solved with Go, c++]
    day-82 - Tidy Numbers - [Already solved with Go, c++]
    day-83 - Bathroom Stalls - [Already solved with Go, c++]
    day-84 - Vestigium - [Already solved with Go, c++]
    day-85 - TCP/IP Client and Server - [Already solved with Go, c++]
    day-86 - Way Too Long Words - [Already solved with Go, c++]
    day-87 - Hulk - [Already solved with Go, c++]
    day-88 - Hit the Lottery - [Already solved with Go, c++]
    day-89 - Minutes Before the New Year - [Already solved with Go, c++]
    day-90 - Radio Station - [Already solved with c++]
    day-91 - Cyberpunk 2078 - [Already solved with c++]
    day-92 - New Year Candles - [Already solved with c++]
    day-93 - Dreamoon and Stairs - [Already solved with c++]
    day-94 - Superhero Transformation - [Already solved with c++]
    day-95 - Free Cash - [Already solved with c++]
    day-96 - Beautiful Paintings - [Already solved with c++]
    day-97 - Elephant - [Already solved with c++]
    day-98 - Geography of Brazil - [Already solved with c++]
    day-100 - Final Hello World - [Already solved with c++]
    day-99 - How is the Weather? - [Already solved with c++]


If you want to be part of the challenge ranking, you need to submit a pull request to be validated by the project contributors. The PR must have the label

and the title of the PR must include the challenge you are submitting (e.g. day-10), otherwise no points will not be added to the ranking. After review, if everything is fine with your PR, the branch will be merged into the
and the ranking generator automated pipeline will run everyday at 22:00PM (Amsterdam time) or when triggered manually, to update the README file.

Check bellow the current ranking:

| RANKING | CONTRIBUTOR | CHALLENGES COMPLETED | TOTAL POINTS | |---------------------|---------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------| | :trophy: 1 | acanova | day-100,day-99,day-98,day-97,day-96,day-95,day-94,day-93,day-92,day-91,day-90,day-89,day-88,day-87,day-86,day-85,day-84c,day-83,day-82,day-81,day-80,day-79,day-78,day-77,day-76,day-75,day-74,day-73,day-72,day-71,day-70,day-69,day-68,day-67,day-66,day-65,day-64,day-63,day-62,day-61,day-60,day-59,day-58,day-57,day-56,day-55,day-54,day-53,day-52,day-51,day-50,day-49,day-48,day-47,day-46,day-45,day-44,day-43,day-42,day-41,day-40,day-39,day-38,day-37,day-36,day-35,day-34,day-33,day-32,day-31,day-30,day-29,day-28,day-27,day-26,day-25,day-24,day-23,day-22,day-21,day-20,day-19,day-18,day-17,day-16,day-15,day-14,day-13,day-12,day-11,day-10,day-09,day-08,day-07,day-06,day-05,day-04,day-03,day-02,day-01 | 10000 | | :2ndplacemedal: 2 | IAPOLINARIO | day-89,day-88,day-87,day-86,day-85,day-84,day-83,day-82,day-81,day-80,day-79,day-78,day-77,day-76,day-75,day-74,day-73,day-72,day-71,day-70,day-69,day-68,day-67,day-66,day-65,day-64,day-63,day-62,day-61,day-60,day-59,day-58,day-56,day-57,day-55,day-54,day-53,day-52,day-51,day-50,day-49,day-48,day-47,day-46,day-45,day-44,day-43,day-42,day-41,day-40,day-39,day-38,day-35,day-37,day-36,day-34,day-33,day-32,day-31,day-29,day-30,day-28,day-27,day-26,day-25,day-24,day-23,day-22,day-21,day-20,day-19,day-18,day-17,day-16,day-15,day-14,day-13,day-12,day-11,day-10,day-09,day-08,day-07,day-06,day-05,day-04,day-03,day-02,day-01 | 8900 | | :3rdplacemedal: 3 | nucci | day-20,day-19,day-18,day-17,day-16,day-15,day-14,day-13,day-12,day-11,day-10,day-9,day-8,day-7,day-6,day-5,day-4,day-3,day-2,day-1 | 2000 | | :seenoevil: 4 | evmartinelli | day-18,day-17,day-16,day-15,day-14,day-13,day-12,day-11,day-10,day-09,day-08,day-07,day-06,day-05,day-04,day-03,day-02,day-01 | 1800 | | :hamburger: 5 | diogotorres | day-08,day-07,day-06,day-05,day-04,day-03,day-02,day-01 | 800 | | :seenoevil: 6 | jaumzors | day-08,day-07,day-06,day-05,day-04,day-03,day-02,day-01 | 800 | | :speaknoevil: 7 | stefanholdermans | day-04,day-3,day-7,day-6,day-5,day-2,day-1 | 700 | | :worried: 8 | fzavalloni | day-06,day-05,day-04,day-03,day-02,day-1 | 600 | | :ghost: 9 | muclemente | day-06,day-05,day-04,day-03,day-02,day-01 | 600 | | :imp: 10 | uigormarshall | day-03,day-02,day-01 | 300 | | :seenoevil: 11 | lucaslra | day-03,day-02,day-01 | 300 | | :cool: 12 | rschio | day-02,day-01 | 200 | | :hearno_evil: 13 | mbertoluci | day-02,day-01 | 200 | | :hamburger: 14 | williamgeduc | day-01 | 100 |

Last Update: 2021-03-02 22:12:03.146679034 +0000 UTC m=+9.971094366

Original Idea

Check out the #100DaysOfCode Project. Changing your habits you are changing your life. Remember that the best time to start is always NOW.

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