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Intermediate1 qubitpar 2

Undo the Hadamard

This circuit was meant to leave the qubit exactly where it started — H, then H again, is the identity. Someone slipped an extra gate into the middle and now it lands on |1⟩ every time. Repair it: |0⟩ with certainty. Click a placed gate to remove it.

Stuck on the concept? Read Interference: Where the Power Comes From.

What you are aiming at100 %
|0⟩
|1⟩
What you are producing right now100 %
|0⟩
|1⟩
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
3
Par
2
Pick a gate from the palette to start building.

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.