Exercises and Assignments
Pen and Paper: Build it, Break it, and Build it Back
Nine stations, a table of cable costs, and an attacker who gets to delete one of them. You build the cheapest grid that connects all nine, work out how much of it survives each possible failure, find the station the attacker will pick, then pull the stations out one at a time — once in an accidental order and once in the attacker’s — and draw the two curves side by side. Finally you redesign the grid, first with the same number of cables and then with four extra, to make that attack as weak as you can.
Do this before the coding notebook. The connectivity and the attack ordering that the notebook computes for you, you will already have worked out by hand on nine stations.
Build a Network, Then Break It
Twelve towns, no cables, and a budget of twenty: click two towns to lay a cable between them, spend the budget however you like, then run a random failure or a hub-first attack on your own design and watch the largest surviving piece shrink. Every attack you run stays on the chart, so you can put two wirings side by side. Twelve towns, twenty cables.
Questions to consider:
- Spend all twenty cables on a ring plus a few chords, so every town has about the same number. Then spend all twenty on two towns. Which wiring has the higher R under random failure? Under targeted attack?
- Can you build a wiring that beats both of those under targeted attack?
Assignments
Pair Notebook
Work through this module with the AI tutor and hand in the notebook that the session builds. What is graded is your reasoning, not your code — see the Pair Notebook guide for the setup and a walkthrough of a full session.
- Repository for M03: coming soon. Your invitation link arrives through Classroom 50.
Group Mini-Project
Who gets the vaccine, and who gets the phone call? Groups of up to three, ninety minutes in class. There is no Classroom assignment and no repository waiting for you this time: the whole thing is one marimo notebook you download and run, and you hand it in through a form.
A disease is loose in five networks and you are short of everything. First you hand out doses for 10% of a town with the whole map in front of you. Then the outbreak is already running, it is found once 10% are infected, and all you hold is the list of cases and the people they named on the phone. Same question both times, and almost none of the same information.
You fill four cells. Two of them describe your algorithm in English and two of them are the code, and the English ones are what is graded — the code may be written by your coding agent from your description, which is exactly why the description has to be precise.
- The task sheet — read it before the session.
- The notebook — the sheet gives the two commands that open it.
You hand in one submission per team at https://go.skojaku.com/m03mini.
Readers who are not enrolled in SSIE 641 cannot open the assignment repositories. The worksheet above and the hands-on notebook cover the same material and need no enrollment.