Hi @user1406 and welcome to the CS50 community. Here you go,
In order to declare a new variable, in the variables palette, click "Make a Variable". A box will appear. Type the name of the variable you want to create, and select weather it should be "for all sprites" (global) or "for this sprite only" (private). Press OK. The image of the button looks like:
according to http://wiki.scratch.mit.edu/wiki/Script:
A script is a collection or stack of blocks that all interlock
with one another. The blocks and their order are very important, as
they determine how sprites interact with each other and the backdrop.
Sometimes, comments are attached to scripts to explain what certain
blocks do and what the ...
What you are seeing is subtle problem called a 'race condition' which is encountered quite often in programming, especially in asynchronous programs like yours.
At the moment your program is designed so that bolt will remove itself when it touches a bat. The bat also removes itself when it touches the bolt. This should work in theory, but it requires that ...
PSet0 just shows like that. It sounds like everything is ok with your submission. Check back again in 2 weeks and if you don't have a grade you will know there was an issue. If you see the picture included, I have no listed submission for pset0 either, but on the grade book page I have a grade.
Scratch is only used for pset0 and next week, you'll be moving onto the C language and Scratch will no longer be mentioned.
You really should complete it before submitting, so perhaps something simpler for now? You could always come back to it later as you learn more programming concepts. Pset0 is meant to be a way to "get your feet wet" and start thinking ...
In your're script window, when the Scratch game is running, you can actually see what script is running. From this, you can see that the Dragon is not moving to the original position because "when I receive 'MoveD'" script remains active, even after "Hippo" starts to move back.
This is, most likely, because the Hippo touches first the Dragon, it sends "...
I think the course defines itself as "introduction to the intellectual enterprises of computer science and the art of programming." It is indeed an art, there are people with an enormous talent for it, as there are for painting, mathematics or chess. Some of the most brilliant minds in history are dedicated to the creation of algorithms, from Eratostenes to ...
Problem sets are graded on a scale of 0 to 1 (0 to 100%), based on the number of checks vs the number you passed. You need at least 0.6 (60%) on each pset in order to qualify for the certificate.
The only feedback you will receive is from check50 that you can run in the appliance to check your work before submitting.
Did you run check50 on your mario and ...
You probably may browse some projects on Scratch to get inspired. Here are some projects made by CS50 students this year. I think I'm not a good game developer. So I thought about stimulating something in the real life. I made this!
Head to http://scratch.mit.edu/ and sign up for an account on MIT’s website by clicking Join Scratch atop the page.
Your mission is, quite simply, to have fun with Scratch and implement a project of your choice (be it an animation, a game, interactive art, or anything else), subject only to the following requirements.
Your project must have at least two ...
If you're using edx, the videos posted on there have subtitles. Go to Week 0 > Shorts (or click here) and click one of the options on the top bar. I don't see the fourth video listed, however. Found a walkthrough (may be different, though) by browsing the files where the others were posted. You can find the download links for the videos here.
You can ...
I had the same issue at the login creen saying my email and password were incorrect.
In my case, it was because I signed in to edX with my google account. Maybe it has issues calling up my account/password with the extra handoff to google.
What I did was sign up for an edX account (instead of logging in via google or yahoo). Fortunately, this was my ...
There is no default option to know when a clone is clicked but you can simulate this feature using something like this in the page of the original sprite.
What this does is that when a clone of the sprite is created, always checks if the mouse is clicked and is touching the clone at the same time. If the condition is true then the clone is deleted. Notice ...
The problem is that the condition Lifes = 0 is only checked once, when the game starts. At that point in the game Lifes = 3, always, so the first condition is ignored because it is false, and the else statement is triggered, which leads to an infinite loop for the rest of the game.
In order to fix your script, you must check if Lifes = 0 throughout the ...
Yes, you can. The final deadline is 31 Dec 2014.
pset0 isn't submitted through the submit page. The instructions are listed at the end of the pset.
How to Submit
To submit this problem set, head to the URL below.
You’ll find that a few questions await. Be extra-sure that your answers are correct, particularly your email ...
The problem is caused by "Sprite 21". There's a script that says
if disappear is 18
The problem is that even after the message is broadcasted, disappear is still 18 and the forever block is still working.
It usually takes up to two weeks for your submissions to get graded. Sometimes they can be graded even within days. If more than two weeks have passed you may want to send an email to Rob Bowden at firstname.lastname@example.org with your edX name and email and also a description of your problem. You can check whether your submission has been grated at http://apps.cs50....
I would suggest exploring other peoples scratchs to help inspire you and so you can see the different types things the program can do. Also, look at the different sprites the program has and maybe one (or more) will inspire you.
From the problem set:
To submit this problem set, visit http://cs50.edx.org/2015/psets/0/.
You’ll find that a few questions await. Be extra-sure that your
answers are correct, particularly your project’s URL on MIT’s website,
lest we overlook your submission!
Scratch sounds can only be mp3 format, so you probably need to convert the turkey sound to mp3. I happened to use Media Monkey to convert it, but I'm sure there are a number of online solutions. [Source]
In the editor window, you can always move sprites around with them mouse in order to set their initial position. This is because you are the programmer, and you are editing the sprites.
However, outside of the editor, you can only interact with the program in ways that are defined by blocks. In the program window, you are the user, and you are not allowed ...