CS6130 Advanced Graph Algorithms

Date Topic Reference Slides Link
Jan 17 Introduction + Administrative announcements None Slides Link
Jan 18 Max-Flow Problem, definition of flow, value of flow. CLRS Ch. 26.1 Slides Link
Jan 19 Residual Network, augmenting the flow, Ford Fulkerson method. CLRS Ch. 26.2 Link
Jan 21 Flows and Cuts, Capacity and Netflow across a cut. Relation to max-flow value, max-flow min-cut Theorem. CLRS Ch. 26.2 Slides Link
Jan 24 Proof of max-flow min-cut theorem, Different ways to obtain min-cut, what if min-cut is unique? CLRS Ch. 26.2 Link
Jan 25 Edmonds Karp algorithm, using shortest paths and a strongly polynomial time algorithm CLRS Ch. 26.2 Link
Jan 28 Matchings, maximal and maximum, alternating and augmenting paths, proof of Berge's theorem Link
Jan 31 Bipartite matchings and Flows, Vertex Covers and Matchings, Konigs theorem and proof via network flows Slides Link
Feb 1 Proof of Konigs theorem, Properties invariant of a maximum matching Link
Feb 2 Dulmage Mendelsohn Decomposition Theorem statement and examples Link
Feb 4 Dulmage Mendelsohn Decomposition Theorem proof via max-flow min-cut Link
Feb 7 Push Relabel Algorithm for computing max-flow CLRS (Sec. 26.4) Kleinberg and Tardos (Sec. 7.4) Link
Feb 8 Push Relabel Algorithm for computing max-flow continued Lecture Notes by Prof. Roughgarden Link
Feb 9 Bounding Number of Relabel and Push operation Slides Link
Feb 11 Variants of Bipartite Matching and Max Flow problem: Reductions. Slides Link
Feb 14 Matchings in General Graphs: Edmonds Algorithm Slides Link
Feb 15 Edmonds Algorithm: Blossom Shrinking Link
Feb 16 Edmonds Algorithm: description, running time Link
Feb 18 Tutte's Theorem Statement, Implications, Setup for GE decomposition Theorem Slides Link
Feb 21 Gallai Edmonds decomposition Theorem and its proof. Link
Feb 22 Gallai Edmonds decomposition Theorem and its proof. Link
Feb 23 Tutte's Theorem (proof). Slides Link
Feb 28 Introduction to Linear Programs, Formulating graph problems as LPs. Slides Link
Mar 1 LPs and Hitting Set problem. Vertex Cover, MST, Shortest paths using Hitting set Link
Mar 2 Linear Programs and Duals. Link
Mar 4 More examples of Duals.
Mar 7 MidSem Discussion. Slides
Mar 8 Weak Duality and Primal Dual Algo for Hitting Set Link
Mar 9 2-approx for vertex cover using Hitting Set. Shortest Path Primal Dual Algorithm. Slides Link
Mar 11 Shortest Path Analysis. Maximum weight matching. Slides Link
Mar 14 Maximum weight matching in bipartite graphs. Link
Mar 15 Perfect Matching polytope for Bipartite graphs Slides Link
Mar 16 Half integrality of the general matching polytope Slides Link
Mar 18 No class: Holi.
Mar 21 Short Quiz2
Mar 22 Matching markets : Introduction to Stable matchings Link
Mar 23 Stable matchings Slides Link
Mar 25 Stability vs. Popularity Link
Mar 28 Popular Matchings modified GS algorithm Link
Mar 29 Popular Matchings continued Link
April 5 Popular Matchings two-sided preferences (proof using LP duality) Paper1 (Sec 2) Paper2 (Sec 3.1) proof of popularity using dual certificate Slides Link
April 6 Two-sided preferences with ties (weakly stable matchings) Paper (Sec 2) Slides Link
Mar 30 Popular Matchings (one-sided preferences)[Lecture by Girija Limaye] Slides Link
April 1 Popular Matchings (one-sided preferences) continued[Lecture by Girija Limaye] Slides Link
April 4 Popular Matchings (one-sided preferences) continued Paper
April 8 & 11 Stable Roommates problem Paper Part1 Part2