Loops · 10 minutes of curiosity

Count down to lift-off.

A while loop repeats as long as its condition is true. It checks before each trip around the loop. Something usually needs to change inside so the loop can eventually stop.

Your mission: while loops & stopping

Start count at 3. While count is greater than 0, say count and subtract 1. After the loop, say Lift-off! Output: 3, 2, 1, Lift-off!

Main mission: 3 → 2 → 1 → Lift-off!
▦ 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.

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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

Change count inside the loop: set count to value of count minus 1. The Lift-off message belongs after the whole loop.

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: Make progress toward a false condition. Stop is always available if a loop runs away. Explore it in Python →

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