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Advanced3 qubitspar 21

One full turn of Grover

Search eight items for the marked one, by hand. Mark |111⟩ with a phase, then run one full diffusion step, so the histogram reads 78.1% on |111⟩ and 3.1% on each of the other seven. That 78.1% is the point: one iteration out of the two that N = 8 wants, and the number is the fingerprint of having actually amplified rather than just written the answer down. Par is 21 gates — this is the longest circuit in the catalogue and it is meant to be.

Stuck on the concept? Read Grover's Search.

What you are aiming at100 %
|000⟩
|001⟩
|010⟩
|011⟩
|100⟩
|101⟩
|110⟩
|111⟩
What you are producing right now100 %
|000⟩
|001⟩
|010⟩
|011⟩
|100⟩
|101⟩
|110⟩
|111⟩
Single qubit
Two qubit
Three qubit
Other

Select a gate to see what it does, then tap a wire — or Tab to a wire and press Enter — to place it.

Gates
0
Par
21
Pick a gate from the palette to start building.

Pick a gate, then tap a cell — or Tab into the grid and use the arrow keys and Enter — to place it.

Generate a fresh target distribution drill at this difficulty. Every generated puzzle is verified solvable by execution before you see it — the generator runs its own solution through the same simulator and grader that will judge yours.