Your code
The code changed since this trace. Press Visualize to trace the new version.
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current
comparing
swapping
visited
done
result
ruled out
Watch algorithms run, step by step, and see where they break.
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Interview prep · Java, Python, C++
Pick a problem and step through it. Arrays, pointers, trees, graphs and DP tables change on screen as the code runs, with the complexity, the key idea, common pitfalls and edge cases you can trace too.
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How this exact code behaves on tricky inputs. Trace any of them to watch it happen.
Questions use your code and the current step as context.