Self-Assessment Quiz: The Quantum Programming Landscape

Twenty questions on the map of the territory. Aim for 16 or more before moving to Chapter 2. Answers and a topic map follow the questions — work the whole quiz first.

Question 1

What does a quantum computer return when you run a program on it? - A. A single classical value, like a classical program - B. A quantum state you can inspect directly - C. A distribution over bitstrings, sampled by repeated execution - D. A probability amplitude for each possible answer

Question 2

The repeated executions of a quantum circuit are called: - A. iterations - B. shots - C. epochs - D. trials

Question 3

Which of these is NOT one of the five major quantum programming frameworks covered in this book? - A. Qiskit - B. Cirq - C. TensorFlow Quantum - D. PennyLane

Question 4

OpenQASM is best described as: - A. a sixth quantum programming framework - B. a quantum assembly language and interchange format - C. IBM's proprietary circuit format - D. a quantum simulator

Question 5

Which framework is built around the idea that a quantum circuit is a differentiable function? - A. Cirq - B. Q# - C. PennyLane - D. Amazon Braket

Question 6

Which framework is the only purpose-built quantum programming language rather than a library embedded in a host language? - A. Qiskit - B. Q# - C. Cirq - D. OpenQASM

Question 7

Cirq's Moment abstraction exists primarily to make which aspect of a program explicit? - A. error rates - B. qubit count - C. simultaneity and timing - D. measurement basis

Question 8

Amazon Braket's distinctive value proposition is: - A. the fastest simulator - B. access to multiple hardware technologies through one SDK - C. the only framework with a type system - D. free unlimited hardware access

Question 9

Which function was removed in Qiskit 1.0, breaking most pre-2024 tutorials? - A. QuantumCircuit() - B. transpile() - C. execute() - D. measure()

Question 10

How many complex amplitudes describe the state of an $n$-qubit system? - A. $n$ - B. $2n$ - C. $n^2$ - D. $2^n$

Question 11

Approximately where does exact statevector simulation on classical hardware become infeasible? - A. around 10 qubits - B. around 20 qubits - C. around 40 to 50 qubits - D. around 500 qubits

Question 12

The no-cloning theorem prevents which classical programming technique? - A. recursion - B. saving a state and restoring it later - C. looping - D. type checking

Question 13

Why is majority-vote error correction unavailable in quantum computing? - A. It is too slow - B. It requires copying an unknown quantum state, which no-cloning forbids - C. Quantum errors are always fatal - D. It requires measurement, which is not supported

Question 14

Measuring a qubit in superposition: - A. leaves the state unchanged - B. collapses it to a definite value, permanently - C. copies it to a classical register without disturbance - D. is impossible on real hardware

Question 15

Because measurement destroys the state, the classical debugging technique that becomes unavailable is: - A. setting a breakpoint - B. printing intermediate values - C. writing a unit test - D. reading a stack trace

Question 16

The process of rewriting your circuit into the gates a specific processor physically implements, mapped onto specific physical qubits, is called: - A. compilation to bytecode - B. transpilation - C. serialization - D. linking

Question 17

Why does transpilation matter more than classical compilation for correctness? - A. Transpilers are less reliable - B. Every added gate adds error and every added nanosecond adds decoherence, so a poor transpilation returns noise rather than a slow answer - C. Transpilation can change the algorithm - D. It does not; the analogy is exact

Question 18

NISQ stands for: - A. Networked Intermediate-Scale Quantum - B. Noisy Intermediate-Scale Quantum - C. Non-Interacting Superposition Qubits - D. Native Instruction Set for Quantum

Question 19

To estimate a probability to within $\pm\epsilon$, the number of shots required scales roughly as: - A. $1/\epsilon$ - B. $1/\epsilon^2$ - C. $\log(1/\epsilon)$ - D. $\epsilon^2$

Question 20

Which is the strongest near-term application of quantum computing according to this chapter? - A. breaking RSA encryption - B. combinatorial optimization - C. simulating small molecules - D. quantum machine learning on natural datasets

Answers

# Answer Why
1 C The output of every quantum program is a histogram built from repeated sampling. §1.1
2 B "Shots" is the term throughout the field and throughout this book. §1.1
3 C TensorFlow Quantum is a real library built on Cirq, but it is not one of the five this book covers. §1.2
4 B Assembly-level circuit representation and the interchange format between frameworks. §1.2
5 C PennyLane's QNode makes a circuit behave like a differentiable Python function. §1.2
6 B Q# has its own type system, syntax, and compiler; the others are libraries. §1.2
7 C A Moment is a time slice of simultaneous operations — timing is first-class in Cirq. §1.2
8 B Superconducting, trapped-ion, and neutral-atom devices through one interface. §1.2
9 C execute() was removed in Qiskit 1.0 (Feb 2024), along with QuantumCircuit.qasm(). §1.2 Version Note
10 D One amplitude per bitstring, and there are $2^n$ bitstrings. §1.4
11 C 40 qubits is ~16 TiB; 50 is ~16 PiB. The wall sits in that range. §1.4 Math Aside
12 B No operation copies an unknown quantum state, so there is no checkpoint/restore. §1.4
13 B Storing three copies requires cloning. QEC had to be invented from a different direction. §1.4
14 B Collapse is permanent, and the rest of the computation proceeds from the collapsed state. §1.4
15 B There is no print(qubit). Chapter 26 covers what replaces it. §1.4
16 B Qiskit's term; other frameworks say "compile." §1.1, §1.3
17 B A poorly transpiled circuit does not run slowly — it returns noise. §1.3
18 B Preskill's 2018 term: enough qubits to be interesting, far too much noise for error correction at scale. §1.5
19 B Ten times the precision costs a hundred times the shots. This governs near-term economics. §1.4
20 C Molecules are quantum systems, so the encoding is natural rather than forced. §1.5

Topic Map

Questions Topic Section If you missed these
1, 2, 19 Probabilistic output and shots §1.1, §1.4 Reread §1.1's "three questions" and §1.4 item 1 — this is the most important idea in the chapter
3–8 The five frameworks §1.2 Skim §1.2's code samples again; you do not need to know the frameworks yet, only who they are
9 API churn §1.2 Version Note Important practically: check the date on any quantum code you find
10, 11 The exponential wall §1.4 Math Aside Run the script in Exercise 1.9; the numbers land harder than the argument
12, 13, 14, 15 The four structural differences §1.4 Reread §1.4 in full. Every one of these has a chapter downstream of it
16, 17 Transpilation §1.3 Preview Chapter 10
18, 20 Current capabilities §1.5 This is the section to be able to speak from; reread the Honest Assessment callout

Score 16+: you have the map. Go to Chapter 2.

Score 12–15: reread §1.4 and §1.5. Those two sections carry the ideas the rest of the book depends on; the framework trivia in §1.2 matters much less right now.

Score under 12: reread the whole chapter, but do not stall here. This is a survey — much of it will land retroactively once you have run something. Go to Chapter 2, run a circuit on real hardware, and come back to this quiz afterward. It will read very differently.