Advanced Algorithms
A foray into measured compromises.
When we think about designing algorithms, we are usually very demanding in how we go about it: we require our algorithms to be fast and accurate on all conceivable inputs.
This is asking for quite a bit, and perhaps it is not surprising that we cannot afford this luxury all the time. The good news is that most of the time we can make meaningful progress by relaxing just one of these demands.
This course will survey three broad themes in this direction:
- suppress the demand for an exact answer (randomized and/or approximation algorithms)
- do not insist on solving the problem on all conceivable instances (parameterized algorithms and algorithms for special classes of input)
- give up on speed (exact and/or parameterized algorithms)
Announcements
28/01 · Tomorrow’s lecture will be a guest lecture by Arjun Arul on the hardness of 3-COL and Subset Sum.
08/03 · The next two classes will be guest lectures by Venkatesh Raman and will offer an introduction to the parameterized paradigm.
23/03 · The next two classes will be guest lectures by Arjun Arul on FAST and chromatic coding.
25/03 · Some notes and problems have been added to this website.
03/04 · Course feedback is scheduled on the 16th of April.
05/04 · Quiz 3 and Quiz 4 are now available and due next Sunday, 12th April, midnight. I will share the details of how to submit soon.
2026 · Jan-Apr Term (IITGN)
Lecture Plan
| Date | Topic |
|---|---|
| 06 Jan, 2026 | Week 1: Introduction and Overview - I · Slides |
| 08 Jan, 2026 | Introduction and Overview - II |
| 13 Jan, 2026 | Week 2: Interval Scheduling · Slides |
| 15 Jan, 2026 | Matroids · Correctness of Greedy |
| 20 Jan, 2026 | Week 3: Realistic Sets · Graphic Matroids |
| 22 Jan, 2026 | Sports Elimination via MaxFlow |
| 27 Jan, 2026 | Week 4: Elections to MinCut · SAT to Independent Set |
| 29 Jan, 2026 | Hardness of 3-COL and Subset Sum |
| 03 Feb, 2026 | Quiz 1 |
| 05 Feb, 2026 | Week 5: PSPACE · Relating COL and NoGo |
| 10 Feb, 2026 | Week 6: Hardness of Geography · Randomized QuickSort |
| 12 Feb, 2026 | No Class |
| 17 Feb, 2026 | Week 7: Polynomial Identity Testing · Counting Matchings |
| 19 Feb, 2026 | Karger’s Algorithm for Mincut · 2-approx for Maxcut |
| 20 Feb - 07 Mar | Midsem Break · Quiz 2 |
| 10 Mar, 2026 | Week 8: Parameterized Algorithms |
| 12 Mar, 2026 | Branching Algorithms and Kernelization |
| 17 Mar, 2026 | Week 9: Iterative Compresssion for FVS |
| 19 Mar, 2026 | Color Coding for Long Path |
| 24 Mar, 2026 | Week 10: Kernel for FAST |
| 26 Mar, 2026 | Chromatic Coding for FAST |
| 31 Mar, 2026 | Holiday - No Class |
| 02 Apr, 2026 | Week 11: Approximation via Greedy |
| 07 Apr, 2026 | LP Rounding and Primal-Dual Methods |
| 09 Apr, 2026 | Week 12: Randomized Rounding - I |
| 14 Apr, 2026 | Randomized Rounding - II |
| 16 Apr, 2026 | Week 13: Hardness Frameworks (ETH, SETH) |
| 21 Apr, 2026 | Hardness Frameworks (PCP, UGC) |
| 23 Apr, 2026 | Quiz 5 |
Grading Policy
There will be six quizzes, each worth 20 points. Your total score will be capped at 100. No re-exams.
Quiz 2 and Quiz 6 will be held during the midsem and endsem exam weeks respectively. Sample questions will be added here in due course. Quiz 3 and Quiz 4 will be take-home.
References
Parameterized Algorithms Marek Cygan, Fedor V. Fomin, Łukasz Kowalik, Daniel Lokshtanov, Dániel Marx, Marcin Pilipczuk, Michał Pilipczuk, and Saket Saurabh Springer, 2015 Book website | Springer
The Design of Approximation Algorithms David P. Williamson and David B. Shmoys Cambridge University Press, 2011 Book website (free PDF) | Cambridge
Probability and Computing: Randomization and Probabilistic Techniques in Algorithms and Data Analysis (2nd Edition) Michael Mitzenmacher and Eli Upfal Cambridge University Press, 2017 Cambridge
Exact Exponential Algorithms Fedor V. Fomin and Dieter Kratsch Springer, 2010 Springer