2. Quantum Gates Circuits

Multiqubit Circuits — Quiz

Test your understanding of multiqubit circuits with 5 practice questions.

Practice Questions

Question 1

Which CNOT subcircuit pattern computes the parity of $n$ qubits in depth $O(\log n)$ using additional ancilla qubits?

Question 2

What is the circuit depth to compute the parity of 8 qubits using a balanced binary tree of CNOT gates, assuming sufficient ancilla?

Question 3

When reusing a single ancilla qubit sequentially for parity calculation on $n$ data qubits instead of using multiple ancillas in parallel, what trade-off occurs?

Question 4

Which quantum adder circuit pattern uses a sequence of Toffoli gates that propagate the carry bit through qubits sequentially?

Question 5

The Cuccaro ripple-carry adder implements addition on two $n$-qubit registers and one ancilla qubit. What are its depth and ancilla requirements?