Walkthrough ‐ Hybrid.D: Back‐to‐Front

Learning Objectives

• The player is challenged to transform qubits in a specified manner, but with the restriction that these qubits can only act as control for other quantum gates.
• The successful completion of this task realizes a key component of the Bernstein–Vazirani algorithm (utilized later in level H.D+).

Solution

1. The measurement component on the top rail is set (slightly) closer to anti-alignment with the input qubits. This setting increases the odds of returning a 1 measurement to 69% as desired.
2. On the bottom rail, the first measurement is set to return a 50-50 result. The second two measurements return 50-50 and 0-100 results. This produces the desired 75% of the final measurement results in the 1 state.

Level File (copy then paste into Qubit Factory)

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