18 min · up to 80 XP

Logic and loops

Decisions and repetition: the heart of every program.

Sam's order screen remembers things now. But it treats every moment exactly the same: it can't decide anything, and it can't repeat anything without her copy-pasting lines like a Victorian clerk.

Her AI tutor grins: "Two moves fix both, and honestly, they're most of programming. Warm-up first. Don't run the next four lines. Read them, then tell me what prints."

Predict the response

Sam takes the challenge seriously: predict first, run second. It's the loop from module 0 with the read step turned all the way up.

Before I run it, my prediction attempt. Here's your warm-up: let cups = 3; if (cups > 2) { console.log("Steady on"); } else { console.log("Have another"); } What prints?

What do you think the AI will do?

That's an if/else, a fork where the condition picks the road. The second move is repetition: a loop runs the same block again and again while its condition stays true.

Saturday, and Sam's on coffee duty for three friends, one label per cup. The classic tool is the for loop, three parts in one line: start (let i = 1), check (i <= 3), step (i++, add one). Watch one actually run, this diagram is the debugger's-eye view.

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