(March 11, 2008) I corrected the chapter on Cardinality and Weigh Constraints. Numerous typos were eliminated, but new ones, surely, were introduced.

(March 14, 2008) The chapter on Constraint Satisfaction and SAT has been redone. The proof of Schaefer Theorem was redone along the lines proposed by H. Chen. I started to work on the index for the book.

(April 2, 2008) A new version is complete. New version of introduction, with the description of contents. Complete index provided.

(January 14, 2011) In table 5.4, p. 79 there are several typos. Specifically: in the header of the table first x\cdot z should be x\cdot y, and then, the header of the last column should be: (x\cdot y ) + (x\cdot z)

On p. 39, line 14, instead of "set of formulas S" it should be "set of formulas F" (it is not incorrect, just bad math writing)

(February 27, 2011) I the proof of Corollary 7.6, p. 110, line -4, a
clarification is needed. Specifically, instead of:

`So the only possible clause from \Var_{\Res(F)} subsuming p is empty.'

we should write

`So the only possible clause with variables from \Var_{\Res(F)} subsuming p is
empty.'

(February 27, 2011). In the proof of Quine Theorem (p. 111) the directions are mixed up (lines -11, -12). Instead or \Rightarrow there should be \Leftarrow, and conversely as well.

** Set up:** July 25, 2006

** This page last modified:** February 24, 2012