This game is just for fun, but when you see what you can do with the code, you can’t stop thinking about it! Let’s get started… Step 1: Download the code, print it and punch holes. Now, let’s start with some fun. The code below is a game that I was playing around with in Javascript a couple of weeks ago, when it suddenly became clear to me what a powerful concept it is. It’s a game that has you guessing which player did the given line, and makes you think about how you would implement some of the features I did in the game. I think you’ll really like the challenge. The source code for the game is also available on GitHub if you want to learn more about the implementation. Let’s get started. # Game rules The code is written in Javascript and it goes all the way to line 1699. I created a PDF document with the game rules on it, and put it here for you: The rules.pdf The idea is that you have to guess which player did what. After each line, the other players will tell you whether they think you’re right or wrong. When it’s time to guess again, you’ll have to go on with your line, but you have to wait a short moment before you can guess. When you make your guess, you must put your finger on the piece of paper. It is important to learn how to follow the rules, because it’s a lot of fun, but also important to learn why. When it’s a different piece of code, the rules are easy to follow, but when you apply these rules to a function like sin or cos you’ll start to think about why you have to write the code this way. It’s a good learning experience, and it’s an excellent way to practice using functions. You need to make a guess and show your finger to other players before you can read the next line, so no one else can follow your line while you are reading. Don’t worry about putting your finger on a number that’s actually on your line. You can guess something that’s on the line, even if it’s already shown to other players. After you guess a line, you don’t know what the next line will be, so you need to watch out. Make sure to put your finger on the paper before the other players start giving their guess. Here are a few tips. You can ask questions as you go along, but if you think you have the answer, don’t tell anyone until you have put your finger on the paper. Even though it’s a bit harder to do that, you can still keep your finger on the paper to see if the other players can guess your next line. Be sure to get your hands off when someone else shows their hand to you. Finally, you can only guess the line after everyone else has guessed, so your guess is only valid if no one else knows the answer. You’re allowed to make mistakes! Don’t be afraid to make mistakes when guessing – this is the fun part! You can’t read your own line, so if you see what it says you won’t be able to complete it. Try to do it like this: guess yourself. Step 2: Print and punch holes. Now that you have the game source code and the rules, it’s time to have some fun! To play the game, you’ll need to print out the code and punch some holes, so you can fix a game board. You don’t have to go to the store to do this. You can cut out a paper with a marker and punch the holes yourself. You can print the code using a free online tool like this one. Step 3: Mark the lines. Mark the lines, then remove the code so you can put your game board together. To do this, you have to understand some of the rules. We’re looking for two things: You need to find a way to get your finger to a line in the code. It’s easy to guess if you don’t count, so make sure you know how to count, and use the index of the line number that you are on. You have to check the line with something before you can guess the next line. Make sure the line starts with line_ and end with the corresponding end_ character. It’s easiest to check the rules by making a list on paper, so that you’re sure you don’t forget any characters. You can skip this step if you don’t have time or patience, or if it makes the game more fun to leave out something from the code. Step 4: Put it together. Print the code, punch some holes and mark the lines. Then, you can assemble the game board, if you haven’t made it already. Make sure to get a group of people together who can play the game, and who are interested in computer science. Then, you can play the code. You can learn about the game in more detail in the article I wrote about it. You can also find a collection of my other blog posts about computer science games and other fun things to do here, but this one is in particular fun for beginners. The code The code is fairly simple, and you can easily modify it to make it more difficult. The code consists of three sections. There’s the rules, a section that checks if all the rules have been followed and a game control section. Here are some of the rules: Each line starts with the keyword line_ , which marks the start of a new line, and ends with the keyword end_ . You can use other letters or a different name, but don’t use any other character than these. There are many other rules, but these are the most important ones. The game control section is just for managing the game state. You have to initialize the game, and decide when to start and end the game. I recommend giving one person the role of king and having others guess and check the lines. The code is actually easier to read if you run it. It’s much easier to see if the user has put his finger on the right lines, and see if there are other mistakes. You can download a compressed file with the code and the rules, or you can simply run the code on the page on a browser. When you run it, you can even use the developer tools to see the execution in the browser. This is very useful, because it gives you some insight into the execution of the code. You can also give the game as a present, or send it in an e-mail, but be careful to check for spelling mistakes. I had a few typos, so I recommend typing it up on a computer and making sure the spelling is correct. If you use the code on your computer, you’ll be able to see the execution, and make sure you didn’t miss anything. When you send the code by e-mail, I recommend that you attach the files to the message so it’s easier to reply. The script in all its glory Check out the code here, or download the archive here. The zip file contains all the files to make it easier for you to play. Just don’t open the code in a browser yet, you need to print the code first. Rules.pdf (the PDF is attached to the ZIP file) The game board (the PNG file is attached to the ZIP file) The code (the zip file) The game board (the PNG) Make sure to print and punch holes, and put a copy of the rules and the game board in an envelope, because it makes a great gift!