Final Exam Information

Written by Nick Troccoli, Jerry Cain and Lisa Yan, based on documents by Julie Zelenski and others

Date/Time/Location:

Friday, March 24th, 8:30-11:30AM in Dinkelspiel Auditorium

Overview

The final exam will be held during our registrar-scheduled exam time: Friday, March 24, 8:30-11:30AM. The exam is designed to assess your mastery of the course learning objectives, with a particular emphasis on material that was prominent in the lectures, assignments and labs.

The exam is closed-book. You may bring a double-sided US-Letter-sized (8.5"x11") page of your own prepared notes. The exam will include a reference sheet of essential details such as prototypes for standard library functions (e.g., strcpy, strlen, malloc), commonly used constants, as well as an additional reference sheet with the common x86-64 assembly instructions. You will take your exam on paper.

Please make sure to thoroughly read all information contained on this page to ensure you understand the midterm logistics, requirements and restrictions.

Logistics

The exam is closed-book. You may bring a double-sided US-Letter-sized (8.5"x11") page of your own prepared notes. The exam will include a reference sheet of essential details such as prototypes for standard library functions (e.g., strcpy, strlen, malloc), as well as an additional reference sheet with the common x86-64 assembly instructions.

Course staff will be proctors at the exam to answer clarification questions.

The exam is strictly individual work.

During the exam, you may use/reference:

a double-sided US-Letter-sized (8.5"x11") page of your own prepared notes.
a provided reference of essential details such as prototypes for standard library functions (e.g., strcpy, strlen, malloc) and common x86-64 assembly instructions. This is included in the exam.
provided blank scratch paper (we will provide this at the exam)

You are not permitted to use any other materials, such as printouts (notes, slides, code, practice exams, etc.), other textbooks, or electronic devices (iPads, Kindles, calculators, music players, etc.).

The exam may be a mix of short answer, multiple choice, code reading, code writing, etc. questions.

Material Covered

The final is intended to assess your understanding of the content covered throughout the course. The priority is on material that figured prominently in the assignments, labs, lecture, and reading (this list is in order of decreasing emphasis). The topic coverage for the final exam will be comprehensive and span the entire quarter, but expect more emphasis on material covered after the midterm (i.e. >= lab4 and assign4, since assign4 was only lightly covered on the midterm).

We highly recommend revisiting the labs and assignments. Each of them contain post-task self-check questions at the end that you can use to review. The B&O textbook also contains many exercises if you want additional problems to work.

We'd love to see the discussion forum come alive in helping everyone do their best on the exam – this is a great place to ask and answer unresolved questions, discuss conceptual issues, share techniques and materials you are finding useful as preparation, and support and encourage each other.

Topics Summary

Check your rear-view mirror for the very impressive list of things you've learned in 107!

All about C and memory: C—strings, arrays, pointers, void*, pointer arithmetic, typecasts, function pointers, generics, stack and heap
Data representation: bits, bytes, ASCII, two's complement integers, pointers, aggregate types (arrays and structs)
x86-64 assembly: data access and addressing modes, arithmetic and logical ops, implementation of C control structures, call/return
Address space: layout and purpose of text/data/stack/heap segments, handling of different variable scopes/types
Runtime stack: caller/callee protocol, parameter passing, use of registers
Memory and heap: stack versus heap allocation, heap allocator strategies and tradeoffs
Performance: compiler optimizations, profiling
Optimization
Topics from CA lectures during the last two weeks of class

What To Bring

The exam is on paper. You should bring:

Pencils / pens
your physical double-sided page of notes

Honor Code

The exam is to be completed individually and without any assistance from a partner or other students. Follow the Stanford Honor Code (see link on main course homepage) during the exam: submit only your own work, do not use unpermitted aids on the exam, and say something to the instructors or students in question to prevent any inappropriate activity conducted by others surrounding the exam.

Grading

(Same as midterm exam)

For coding questions, the majority of the points are typically focused on the correctness of the code. However, there may be deductions for code that is roundabout, awkward or inefficient when more appropriate alternatives exist. We will reward the simple, direct approach for its good design decisions and such code will likely have fewer correctness issues, so the choice of appropriate design can have a large impact. For example, we expect you to leverage appropriate features from the standard libraries; re-implementing that functionality wastes your valuable time and introduces opportunity for error.

Note that certain problems may have certain constraints (such as only using certain material, etc.) that you must follow to earn full credit. These constraints are not intended to make things difficult; typically, we are trying to guide you in the direction of a more straightforward solution. If you disregard these instructions, you are likely to lose points, either for not meeting the problem specification and/or for errors introduced when attempting a convoluted alternative. We reserve the right to deduct points for extremely inelegant or inefficient code that dodges the spirit of the problem.

You are not required to write #include statements. Please do not abbreviate any code (such as writing "x2" next to code to copy it twice). Abbreviated code will not be graded.
Pseudo-code (writing English sentences and phrases instead of code) will typically earn little to no points. For example, writing "In this part of the code, I want to open the file and read each line and print it" will not earn any points.
You should include your answer, as well as any scratchwork, in the text area for each problem. An answer to a problem not in the designated answer pages for that problem will not receive any credit.
Unless otherwise specified, it is fine to write helper functions to implement the required behavior.
Style and decomposition are secondary to correctness. Unlike the assignments where we hold you to high standards in all areas, for an exam, the correctness of the answers dominates the grading. Decomposition and style are thus somewhat de-emphasized. However, good design may make it easier for you to get the functionality correct and may require less code, which takes less time and provides fewer opportunities for error. Comments are never required unless specifically indicated by a problem. When a solution is incorrect, commenting may help us determine what you were trying to do when we attempt to give partial credit.
We are lenient on syntax. We won’t trouble you about most small syntax errors (forgetting semicolons or spaces, for example) as long as your intentions are clear. Having said that, beware that if your syntax errors cause ambiguity (e.g. very unclear curly braces), we might not get the correct meaning. Additionally, there are subtleties that matter immensely, e.g., a int** is just one character different than int*, yet there is a world of difference between the two!
The majority of the points for a problem will be reserved for grading the critical core of the code. For example, if we ask you to write a function that processes a generic array, only a tiny fraction of the points will be allocated to tasks such as initializing the counter or iterating over the right bounds, while the bulk of the points will be gained or lost in the tricky details of whether you correctly handle the void*s. Being off-by-one in the loop is a tiny deduction, but being a level of indirection off or applying the wrong cast is a larger issue. Be sure to focus your attention accordingly!

Exam Reference Sheets: Note: the reference sheets are included in the exam. You will be provided with hard copies as well during the exam.

C Reference Sheet Webpage | C Reference Sheet PDF
(This is the same reference sheet as on the midterm exam, but also includes some defined constants you may need)

Assembly Reference Sheet
(This is the same assembly reference sheet we have used in class and labs)

Practice Materials:

Guide for how to approach and succeed on CS107 exams.

Note: some of the exams include questions covering floats, which is not included this quarter on our final exam topics.

Practice Exam 1: PDF | Solutions
This is based on the final exam from CS107 Winter 2018. It was written as a 180 minute exam (the same as this quarter).

Practice Exam 2: PDF | Solutions
This is based on the final exam from CS107 Fall 2017. It was written as a 180 minute exam (same length as this quarter).

Practice Exam 3: PDF | Solutions
This is based on the final exam from CS107 Fall 2018. It was written as a 180 minute exam (same length as this quarter).

Extra Practice Problems: PDF | Solutions