6.890 Algorithmic Lower Bounds: Fun with Hardness Proofs (Fall '14)

Prof. Erik Demaine TAs: Sarah Eisenstat, Jayson Lynch

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[+] Circuit SAT. Dual-rail logic vs. binary logic; Akari/Light Up, Minesweeper (consistency and inference); planar Circuit SAT; Candy Crush / Bejeweled

This lecture starts with a distinction between two key SAT reduction styles:

Dual-rail logic: variables + clauses (most proofs we've seen)
Binary logic: wires + splitters + clauses (crease pattern proof)
Circuit SAT: wires + splitters + universal gates

Then we will see a few proofs in the Circuit SAT style:

Akari / Light-Up (another Nikoli puzzle)
Minesweeper consistency
Minesweeper inference (which is actually coNP-complete)
Candy Crush and Bejeweled (actually from 3SAT)

Download Video: 360p, 720p

Handwritten notes, page 1/6 • [previous page] • [next page] • [PDF]

Slides, page 1/28 • [previous page] • [next page] • [PDF]

http://arxiv.org/abs/1203.1895

Slides, page 1/28 • [previous page] • [next page] • [PDF]