CSC151.02 2015S, Class 01: An Introduction to Algorithms

Overview

Preliminaries

Welcome to CSC 151! I'm Sam. Your mentors are Alex and Sarah.
Grab a standard playing card.
Grab a blank card and a pen, write your name on the card, illustrate the card if so inclined, and hand both card and pen to a mentor when you are done.
There are no textbooks for the class.
Anything I type in this window will (eventually) show up online.

Assignment 1 due tomorrow night.
- Expect me to take at least a week to respond.
Readings for Wednesday: Grinnell's Linux Environment and Parts of Algorithms

Today, 6:00 p.m., Herrick, Ta-Nehisi Coates, "The Case for Reparations"
Friday, 12:10 p.m., JRC 224A (Day PDR), CS Table, "Computer Programming as an Art" (copies outside my office)

I would like to know
- What name to use for you in less formal situations. This will usually be your given name or a nick name.
- What name to use if I am addressing you by family name or last name.
- Your preferred gender pronoun.
- Optionally, any upcoming events in which you are participating that you would like classmates to attend.
When I call a name that resembles your name, please answer using something like the following models. (It's okay if you don't have any upcoming events.)
- Hi. My name is Casey Smith. I prefer that you call me "Case" or "Mr. Smith". My preferred gender pronouns are he, him, and his. I'm singing in a Con Brio concert this weekend, and I hope to see many of you there, even if you are in favor of toy trains.
- Hi. My name is Casey Smith. I prefer that you call me "Casey" or "Ms. Smith". My preferred gender pronouns are she and her. I'm swimming against cornfolk from the neighboring state on Friday, January 30, and we always like to have folks cheer us on.
- Hi. My name is Casey Smith. I prefer that you call me "Cay" or "Mx. Smith". My preferred gender pronouns are zi and zir. I'm giving a math talk on non-Euclidean combinatorics next Tuesday. I look forward to helping you think differently.

Introduce yourself to the person next to you and try to come up with a definition of computer science.
- One reason I love Grinnell students: There was no delay in you following that instruction.
Programming a computer to get a computer to do what you want it to do. [Programming is a skill, not a discipline.]
Behind the scenes in functional problem solving
Modality of thinking about problem spaces based on how computers work
Has to do with computational work
- Analyze data
- Model processes (e.g., biological processes)
- Dealing with larger amounts of data computationally
"Computationally" - calculating using a bunch of operations
Computer science is the study of algorithms and data structures
- Algorithms: Instructions for calculating solutions to problems
- Data structures: Ways to organize data (typically in support of algorithms)

Get together with people with the same card value.
Write instructions to teach me how to make a nut butter and jam sandwich
Assumptions:
- I know the names of things
- I'm clueless - If you give me ambiguous instructions, I am likely to interpret them differently than you intended
- I'm clueless - If you leave things out, I'll make bad assumptions

When things go wrong, it can be funny!
- Really important to remember. Things will go wrong regularly this semester, and laughing and trying again is the best result.
You generally don't get to see your data in advance, so you need to write algorithms that adapt to the data (or limit the kinds of data that you work with).
"It's hard because we don't know how much you know."
"It's hard because we have to try to write it all in one go."
You need to account for the things that can go wrong.
Watch what happens and troubleshoot.
Be specific.