Visual Lab
Simulations
Every algorithm on this site, running on your input — one step at a time, with the current pseudocode line highlighted and every comparison counted. Pick a chapter, or search for an algorithm.
1 · Type your own input. Every sim has a custom-input box and a Random button — use the exact example from your notes.
2 · Step, don't just play. Use ← → to move one step; read the narration to learn why it happened.
3 · Predict first. Before each step, guess what moves next. The sims ask you to at key moments.
being compared
swapped / written
current / focus
pivot / special
done / final
excluded
No simulation matches that search. Try a simpler word, like “sort” or “tree”.