CS253 HW0: Light Bulb Joke

Purpose

The purpose of this assignment is to make sure that you can follow instructions, login to a Linux system, compile a C++ program, and check in homework. This way, you’re sure that your login and password work before you need them for homework #1. This assignment is not optional.                 

Description

In this assignment, you will write a program called hw0. It will answer the question, “How many CU students does it take to change a light bulb?”                 

Where’s the GUI?

In this class, we build software using cmake and make. We turn in a tar file. You don’t really need to know much about any of those programs—we supply a file CMakeLists.txt that is the data file for cmake, which produces a a file Makefile, the data file for make. All that you need to do is type cmake . once, and make every time afterwards. make will compile your code (if it can) and create an hw0.tar file for you to turn in when you’re finished.                 

“Yeah, but where’s the GUI? How do I edit my code?” Edit it any way you want. Use of a GUI or text editor is not required in this class. If you need help using a text editor, come to me for help.                 

Sample Build

In the following example, what you type looks like this. The percent sign, “%”, is my shell prompt. My CMakeLists.txt is shown as an example. You may copy it verbatim, or create your own, as long as it meets the requirements below.                 

    % cat CMakeLists.txt
    cmake_minimum_required(VERSION 3.14)

    # Using -Wall is required:
    add_compile_options(-Wall)

    # These compile flags are highly recommended, but not required:
    add_compile_options(-Wextra -Wpedantic)

    # Optional super-strict mode:
    add_compile_options(-fmessage-length=80 -fno-diagnostics-show-option)
    add_compile_options(-fstack-protector-all -g -O3 -std=c++14 -Walloc-zero)
    add_compile_options(-Walloca -Wctor-dtor-privacy -Wduplicated-cond)
    add_compile_options(-Wduplicated-branches -Werror -Wfatal-errors -Winit-self)
    add_compile_options(-Wlogical-op -Wold-style-cast -Wshadow)
    add_compile_options(-Wunused-const-variable=1 -Wzero-as-null-pointer-constant)

    # add_compile_options must be BEFORE add_executable.

    # Create the executable hw0 from the source file hw0.cc:
    add_executable(hw0 hw0.cc)

    # Create a tar file every time:
    add_custom_target(hw0.tar ALL COMMAND tar cf hw0.tar hw0.cc CMakeLists.txt)
    % cmake .
    … cmake output appears here …
    % make
    … make output appears here …
    % ./hw0
    Three—one to hold the light bulb and two to debate
    whether an LED or a CFL bulb harms the environment more!

Testing

It is essential that you test what you’ve turned in (the hw0.tar file). Here’s an easy way, where % is my prompt:                 

    % rm -rf testdir
    % mkdir testdir
    % cd testdir
    % tar -xvf ../hw0.tar
    % cmake .
    % make
    % ./hw0
    % cd ..

That’s how the TA will test your program (though they will use a different directory name & location). If this doesn’t compile your program, then you get NO points.                 

    export STACK_FRAME_LINK_OVERRIDE=ffff-ad921d60486366258809553a3db49a4a

Requirements

• You may not use any external programs via system(), fork(), popen(), exec*(), etc.
• You may not use C-style <stdio.h> or <cstdio> facilities, such as printf(), puts(), or putc().
  • Instead, use cout.
• You may not use dynamic memory via new, delete, malloc(), calloc(), realloc(), free(), strdup(), etc.
  • It’s ok to implicitly use dynamic memory via containers such as string or vector.
• The output must end with a newline.
  • Newlines do not separate lines—newlines terminate lines. That means that the last line ends with a newline, as all lines do.
• We will compile your program like this: cmake .; make
  • If that generates warnings, you will lose a point.
    • OK, just half a point, since this is a one-point assignment.
  • If that generates errors, you will lose all points.
• There is no automated testing/pre-grading/re-grading.
  • Test your code yourself. It’s your job.
  • Yes, even if you only change it a little bit.
  • Yes, even if all you do is add a comment.
• You will not be graded on the quality of your humor.
  • However, if you duplicate my example joke, you will lose points.
  • That’s because plagiarism is bad.
  • You can’t copy, even if you do give credit—I require original work.
• Turn in a tar file called hw0.tar containing CMakeLists.txt and a single C++ source file, hw0.cc.
  • Yes, .cc, not .cp, .cxx, .cpp, .CPP, .c++, or .C.
• Your CMakeLists.txt must use at least -Wall every time g++ runs.

How to submit your homework:

Use web checkin, or Linux checkin:                 

    ~cs253/bin/checkin HW0 hw0.tar

How to receive negative points:

Turn in someone else’s work.