GHZ's awkward cousin
This circuit was meant to build the three-qubit W state — one excitation shared equally between the qubits, so |001⟩, |010⟩ and |100⟩ each come up 33.3% of the time and nothing else ever does. It is one gate short: the excitation gets to the third qubit but the second one never lets go of it, so 33.3% is sitting on |110⟩ instead of |100⟩. Add the missing CNOT. Leave the two rotations alone. Their angles are not multiples of π/16 and the θ slider cannot type them back in.
Stuck on the concept? Read Entanglement.
Select a gate to see what it does, then tap a wire — or Tab to a wire and press Enter — to place it.
Generate a fresh fix the bug 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.