CS 3100

Data Structures and Algorithms 2

Announcements, Spring 2026

Mark Floryan (mrf8t@virginia.edu)
Aaron Bloomfield (aaron@virginia.edu)
@github | ↑ |

Coordinate Plane Closure

3D graphs that don't contact the plane in the closure area may proceed as scheduled, but be alert for possible collisions with 2D graph lines that reach the hole and unexpectedly enter 3D space.

xkcd # 2735

Lecture 10: Thursday, February 12th

Office hours
- TA office hours are Mon through Thu, from 5-9 in Rice 442
- Prof. Bloomfield’s office hours Mon 10:30-12 and Thu 12:30-2, in Rice 402, and start this week
- Prof. Floryan’s office hours are Mon 1-2, Tue 9-10, and Wed 12-1 in Rice 203, and start this week
Assignments
- PS3 was due yesterday – how did it go?
- PA2 is out, due next Friday (Fri, Feb 20th)
- PS4 will be out today, due next Wednesday
Midterms (aka quizzes): there was some confusion on our end about when
- Quizzes 1&2 are Tuesday, February 24th, in lecture (the Tuesday before spring break)
- Quizzes 3&4: we are expecting to move to a CBTF; details to follow
  - If on paper,then they are Thursday, April 9th, in lecture
- Final: Saturday, May 2nd, from 7pm - 10pm
Course textbook link is on the Canvas landing page
Today we will continue with divide and conquer

Flow Charts

At 8 drinks, you switch the torrent from FreeBSD to Microsoft Bob. C'mon, it'll be fun!

xkcd # 518

Lecture 9: Tuesday, February 10th

Office hours
- TA office hours are Mon through Thu, from 5-9 in Rice 442
- Prof. Bloomfield’s office hours Mon 10:30-12 and Thu 12:30-2, in Rice 402, and start this week
- Prof. Floryan’s office hours are Mon 1-2, Tue 9-10, and Wed 12-1 in Rice 203, and start this week
Assignments
- PA1 was due last Friday – how did it go?
- PS3 is out, due tomorrow (Wed, Feb 11th)
- PA2 is out, due next Friday (Fri, Feb 20th)
- PS4 will be out Thursday, due next Wednesday
Midterms (aka quizzes): there was some confusion on our end about when
- Quizzes 1&2 are Tuesday, February 24th, in lecture (the Tuesday before spring break)
- Quizzes 3&4: we are expecting to move to a CBTF; details to follow
  - If on paper,then they are Thursday, April 9th, in lecture
- Final: Saturday, May 2nd, from 7pm - 10pm
Course textbook link is on the Canvas landing page
Today we will continue with divide and conquer

Linear Sort

The best case is O(n), and the worst case is that someone checks why.

xkcd # 3026

Lecture 8: Thursday, February 5th

Office hours
- TA office hours are Mon through Thu, from 5-9 in Rice 442
- Prof. Bloomfield’s office hours Mon 10:30-12 and Thu 12:30-2, in Rice 402, and start this week
- Prof. Floryan’s office hours are Mon 1-2, Tue 9-10, and Wed 12-1 in Rice 203, and start this week
- All will be posted on the Canvas landing page
Assignments
- PS2 is due tomorrow
- PA1 is due this Friday
- Upcoming: PS3 will be released today, PA2 released on Friday
Midterms (aka quizzes): there was some confusion on our end about when
- Quizzes 1&2 are Tuesday, February 24th, in lecture (the Tuesday before spring break)
- Quizzes 3&4: we are expecting to move to a CBTF; details to follow
  - If on paper,then they are Thursday, April 9th, in lecture
- Final: Saturday, May 2nd, from 7pm - 10pm
Course textbook link is on the Canvas landing page
Today we will continue with divide and conquer

Dependencies

The prereqs for CPSC 357, the class on package management, are CPSC 432, CPSC 357, and glibc2.5 or later.

xkcd # 754

Lecture 7: Tuesday, February 3rd

Office hours
- TA office hours are Mon through Thu, from 5-9 in Rice 442
- Prof. Bloomfield’s office hours Mon 10:30-12 and Thu 12:30-2, in Rice 402, and start this week
- Prof. Floryan’s office hours are Mon 1-2, Tue 9-10, and Wed 12-1 in Rice 203, and start this week
- All will be posted on the Canvas landing page
Assignments
- PS1 was due Friday – how did it go?
- PS2 is due tomorrow
- PA1 is due this Friday
- Upcoming: PS3 will be released Thursday, PA2 released on Friday
Midterms (aka quizzes): there was some confusion on our end about when
- Quizzes 1&2 are Tuesday, February 24th, in lecture (the Tuesday before spring break)
- Quizzes 3&4: we are expecting to move to a CBTF; details to follow
  - If on paper,then they are Thursday, April 9th, in lecture
- Final: Saturday, May 2nd, from 7pm - 10pm
Course textbook link is on the Canvas landing page
Today we will continue with divide and conquer

Ineffective Sorts

StackSort connects to StackOverflow, searches for 'sort a list', and downloads and runs code snippets until the list is sorted.

xkcd # 1185

Lecture 6: Thursday, January 29th

PS1 is out and now due this Friday (Jan 30) by midnight
PS2 will be out today, and due next Wednesday (Feb 4) by midnight
- Gradescope submission opens up 72 hours before the due date
PA1 is out, due Fri, Feb 6
- Gradescope submissions are open
Midterms (aka quizzes): there was some confusion on our end about when
- Quizzes 1&2 are Tuesday, February 24th, in lecture (the Tuesday before spring break)
- Quizzes 3&4 are Thursday, April 9th, in lecture
- Final: Saturday, May 2nd, from 7pm - 10pm
- If we use a CBTF, quizzes 3&4 and/or the final may have a different format, time, and location
Course textbook link is on the Canvas landing page
Office hours
- TA office hours are Mon through Thu, from 5-9 in Rice 442
- Prof. Bloomfield’s office hours Mon 10:30-12 and Thu 12:30-2, in Rice 402, and start this week
- Prof. Floryan’s office hours are Mon 1-2, Tue 9-10, and Wed 12-1 in Rice 203, and start this week
- All will be posted on the Canvas landing page
Today we will continue with graphs

Lecture 5: Tuesday, January 27th

Snow day!

Weird Unicode Math Symbols

U+2A0B ⨋ Mathematicians need to calm down

xkcd # 2606

Lecture 4: Thursday, January 22nd

PS0 was due yesterday – how did it go?
PS1 is out and due next Wednesday (Jan 28) by midnight
- Gradescope submission opens up 72 hours before the due date
- If you don’t see the course, we need to re-sync the roster; email the course email about this
PA1 will be out this Friday, due two weeks later (Feb 6)
Midterms (aka quizzes): there was some confusion on our end about when
- Quizzes 1&2 are Tuesday, February 24th, in lecture (the Tuesday before spring break)
- Quizzes 3&4 are Thursday, April 9th, in lecture
- Final: Saturday, May 2nd, from 7pm - 10pm
- If we use a CBTF, quizzes 3&4 and/or the final may have a different format, time, and location
Course textbook link is on the Canvas landing page
Office hours
- TA office hours are Mon through Thu, from 5-9 in Rice 442
- Prof. Bloomfield’s office hours Mon 10:30-12 and Thu 12:30-2, in Rice 402, and start this week
- Prof. Floryan’s office hours are Mon 1-2, Tue 9-10, and Wed 12-1 in Rice 203, and start this week
- All will be posted on the Canvas landing page
Today we will continue with graphs

Complexity Analysis

PERPETUALLY OPTIMISTIC CASE: Early in the execution, our research group makes a breakthrough on proving P=NP.

xkcd # 2939

Lecture 3: Tuesday, January 20th

PS0 is out in Canvas’ Assignments, and due tomorrow (Wed, Jan 21) by 11:59 pm
- Gradescope submission opens up 72 hours before the due date
- If you don’t see the course, we need to re-sync the roster; email the course email about this
PS1 will be out Thursday afternoon, due next Wednesday (Jan 28)
PA1 will be out this Friday, due two weeks later (Feb 6)
Midterms (aka quizzes): there was some confusion on our end about when
- Quizzes 1&2 are Tuesday, February 24th, in lecture (the Tuesday before spring break)
- Quizzes 3&4 are Thursday, April 9th, in lecture
- Final: Saturday, May 2nd, from 7pm - 10pm
- If we use a CBTF, quizzes 3&4 and/or the final may have a different format, time, and location
Course textbook link is on the Canvas landing page
Office hours
- TA office hours are Mon through Thu, from 5-9 in Rice 442
- Prof. Bloomfield’s office hours Mon 10:30-12 and Thu 12:30-2, in Rice 402, and start this week
- Prof. Floryan’s office hours are Mon 1-2, Tue 9-10, and Wed 12-1 in Rice 203, and start this week
- All will be posted on the Canvas landing page

Algorithms

There was a schism in 2007, when a sect advocating OpenOffice created a fork of Sunday.xlsx and maintained it independently for several months. The efforts to reconcile the conflicting schedules led to the reinvention, within the cells of the spreadsheet, of modern version control.

xkcd # 1667

Lecture 2: Thursday, January 15th

PS0 is out in Canvas’ Assignments, and due next Wednesday (Jan 21) by 11:59 pm
- Gradescope submission opens up 72 hours before the due date
PS1 will be out next week, due the following Wednesday (1/28)
Midterms (aka quizzes): there was some confusion on our end about when
- Quizzes 1&2 are Tuesday, February 24th, in lecture (the Tuesday before spring break)
- Quizzes 3&4 are Thursday, April 9th, in lecture
- Final: Saturday, May 2nd, from 7pm - 10pm
- If we use a CBTF, quizzes 3&4 and/or the final may have a different format, time, and location
Course textbook link is on the Canvas landing page
Office hours
- TA office hours coming soon, and will start next week (we are targeting Mon-Thu, 5pm-9pm); likely in Rice 442
- Prof. Bloomfield’s office hours TBA, in Rice 402, and start next week
- Prof. Floryan’s office hours are TBA, in Rice 203, and start next week
- All will be posted on the Canvas landing page