|q⟩ Bad Qubits

← Question Bank

Predict the output
On the seeded simulator (seed 4735), this circuit runs for 1024 shots. About how many come out |01⟩? Estimate P(|01⟩) × 1024 and pick the closest option.
⚛ The apparatus
// Start at |00>, flip qubit 1 to get |01>, Hadamard qubit 0 to get
// (|01> + |11>)/sqrt(2), then CNOT(0->1) turns |11> into |10>, giving
// the symmetric triplet (|01> + |10>)/sqrt(2).
const c = circuit(2);
c.x(1);
c.h(0);
c.cx(0, 1);
return c;

Commit your prediction for counts of |01⟩ over 1024 shots — then run it.