Companion module: the C++ Foundations module is the complete, enriched version of this unit’s material — study these pages together for extra depth, practice sets, and the variation lab.</div>

Quiz 01 — Answer Key

The explanations are the lesson · Quiz · Unit index

Q1 — b. A compiler translates your source file into machine-code instructions and writes them to an executable file. (a) describes an interpreter — a different execution model, not what g++ does; (c) and (d) confuse the compiler with other tools in the toolchain. It’s worth being precise here: “the compiler” and “the terminal” are different programs doing different jobs.

Q2 — c. The course’s standard line: standard (-std=c++17), warnings (-Wall -Wextra), source file (card.cpp), output name (-o card). (a) isn’t a command that exists; (b) compiles but (i) without our warning flags and (ii) produces a default-named executable (a.out / a.exe), not card; (d) jumbles -o with the source name — -o expects the output name right after it.

Q3 — a. Execution of every C++ program starts at the function main. The other options describe things main does not do — data lives in variables, and compiling is entirely the compiler’s job.

Q4 — False. A comment is ignored by the compiler; it never reaches the executable and never prints. Printing needs std::cout. (Comments exist to explain code to humans.)

Q5 — False — and this one matters. A warning means the compiler can proceed but thinks something looks wrong. It still produces an executable. This course treats warnings as errors to fix immediately, but that’s our discipline, not a compiler limitation.

Q6 — True. The .cpp file is the source (text for humans + the compiler). The executable is the machine-code file you actually run: ./card (Linux/macOS) or .\card.exe (Windows). Running the .cpp does nothing useful.

Q7.

Roses are red
Violets are blue

The first statement has no \n, so Roses and ` are red share a line; each later statement ends with \n`.

Q8.

1       2
3       4

\t jumps to the next tab stop (columns align); \n ends each line. Exact gap width depends on your terminal’s tab stops.

Q9 — line 3, missing ;. The statement std::cout << "Hi\n" is not terminated. Notice the subtlety we practised: the compiler may report the problem at line 4 (expected ';' before 'return') because that’s where it became confused — the mistake is one line above the report. Read upward.

Q10 — b. \b is the backspace escape character. The program compiles cleanly (it’s legal C++ — that’s why no warning fires) and prints Welcome to, backspaces one position, then ` C++. On many terminals you'll see Welcome to C++ with the o` overwritten — clearly not intended. This is your first taste of a logic/typo bug that the compiler cannot catch: it compiles, it runs, and it’s wrong. Only comparing actual output with intended output finds it — which is exactly what the Debug It hunts train.

Scoring: 1 point each. ≥ 9 → Unit 01 complete. 7–8 → revisit the flagged lessons. ≤ 6 → redo the exercises and revision sheet, then retake. (bands)

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