Build & debug · 8 minutes of curiosity

One program. New possibilities.

Input is information your program receives. Processing is what it does with that information. Output is what it gives back. Different inputs can make the same program produce different results.

Your mission: input, processing & output

Read friends from the input panel, multiply it by 2, and print the result. We’ll check 0, 4, and 6 friends.

No friends: 0Four friends: 8Six friends: 12
▦ BLOCK LAB · made for making

Build it: choose a toolbox category, drag blocks onto the canvas, then snap instructions inside when I press Run. Drop values into matching sockets. Edit words or numbers directly on their blocks.

Waking up the blocks…

Projects are saved on this device when storage is available.

Loading the visual editor…
Inputs Try different values

Inputs give your program information. An “input” block reads a value by its exact name. Task checks use their own values.

From blocks to Python A bridge to your next adventure

Generate real Python from these blocks. The helper functions keep Bit’s messages familiar. Python has its own type rules; the Python trail explains them.

Start a fresh plan?

This replaces the blocks on this canvas. Download your project first if you want to keep a copy.

A little hint, please

Use the input friends block instead of a fixed number. Change friends in the panel and run again to test it.

How do I use these blocks?

Pick a category on the left to see its blocks. Drag a block onto the canvas. Instructions connect in a stack inside “when I press Run”. Rounded value blocks go into sockets. Change a field by selecting the word, number, or dropdown on the block.

Use the canvas zoom controls or Fit blocks if a stack goes out of view. Undo can bring back an accidental change. Disconnected blocks do not run. Your canvas saves here on this device.

Pack this idea for later: A program is more useful when it can work with new input. Explore it in Python →

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