n The history of computer programming is a steady move away from machine-
oriented views of programming towards concepts and metaphors that more
closely reflect the way in which we ourselves understand th
The constant sum in every row, column and diagonal is called the magic constant or magic
sum, M. The magic constant of a normal magic square depends only on n and has the value
For normal magic squares of order n = 3, 4, 5, ., the magic const
Parsing Context-Free Grammars
Parsing is search
Top-down and bottom-up parsing
Wednesday, October 17, 2012
Parsing is the process of deriving syntactic structure
of the input (usually, a sentence) using a (formal) grammar.
The processing metapho
The Earley Algorithm
The main idea:
The basic top-down parsing algorithm with bottom-up
filtering (e.g., using the left-corner heuristic) is the basis
for efficient parsing.
The problems of left-recursive rules, ambiguity and
subtree reparsing are tackled
The Cocke-Kasami-Younger (CKY) Parsing Algorithm
This is an efficient bottom-up parsing algorithm that
uses the dynamic programming technique.
CKY can only work with grammars whose rules are more
constrained than those in a canonical CF grammar.
Dr. John E. Dorband
One hour Tuesday & Thursday after class
TA: Satyajit Padalkar <firstname.lastname@example.org>
Monday & Wednesday 3:00 to 4:00
20% - Participation & Homework
30% - Mid-term Test
Grads - 50% - Pro