From the videos

Just watched one of our shorts? Pick it below and open the full lesson: the same idea as an animation you step through, with an exercise and a quiz. Free, no sign-up.

Guess the output · Oct 10
A 3 by 3 grid, one assignment. What does it print?
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Made in code · Oct 10
2,400 birds. No leader.
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Four levels · Oct 9
Is 1,000,000,007 prime? 1 billion divisions, or 4 rounds?
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Algorithm reels · Oct 9
Three pointers. Watch the arrows flip.
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How it works · Oct 8
Your signal drops. Why does the video blur instead of freezing?
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Algorithm reels · Oct 8
One stack. Every bracket. 15 seconds.
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Four levels · Oct 7
fib(50): 40,730,022,147 calls, or 7?
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Algorithm reels · Oct 7
BFS doesn't search. It spreads.
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How it works · Oct 6
You tapped Pay twice. Why only one charge?
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Algorithm reels · Oct 6
Where does your key actually go?
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Guess the output · Oct 5
One function, called twice. What does it print?
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Algorithm reels · Oct 5
5 Big-O classes, slowest to fastest.
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How it works · Oct 4
1,000,000 open sockets. How does a message find yours?
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Made in code · Oct 4
8 sorting algorithms. The same 64 numbers. Who finishes first?
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Algorithm reels · Oct 2
1,000,000 items. 20 steps. Here's how.
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Algorithm reels · Oct 1
One pivot. Watch the array split itself.
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Algorithm reels · Sep 30
This is the one you already do with playing cards.
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Algorithm reels · Sep 29
Same array. Fewer swaps. Why?
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Algorithm reels · Sep 28
Can you sort this in 12 swaps?
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From the videos

A 3 by 3 grid, one assignment. What does it print?

2,400 birds. No leader.

Is 1,000,000,007 prime? 1 billion divisions, or 4 rounds?

Three pointers. Watch the arrows flip.

Your signal drops. Why does the video blur instead of freezing?

One stack. Every bracket. 15 seconds.

fib(50): 40,730,022,147 calls, or 7?

BFS doesn't search. It spreads.

You tapped Pay twice. Why only one charge?

Where does your key actually go?

One function, called twice. What does it print?

5 Big-O classes, slowest to fastest.

1,000,000 open sockets. How does a message find yours?

8 sorting algorithms. The same 64 numbers. Who finishes first?

1,000,000 items. 20 steps. Here's how.

One pivot. Watch the array split itself.

This is the one you already do with playing cards.

Same array. Fewer swaps. Why?

Can you sort this in 12 swaps?

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