Title
A lower bound for integer greatest common divisor computations
Abstract
It is proved that no finite computation tree with operations { +, -, *, /, mod, a and b is one, for all pairs of integers a and b. This settles a problem posed by Gro¨tschel et al. Moreover, if the constants explicitly involved in any operation performed in the tree are restricted to be “0” and “1” (and any other constant must be computed), then we prove an &OHgr;(log log n) lower bound on the depth of any computation tree with operations { +, -, *, /, mod, a and b is one, for all pairs of n-bit integers a and b.A novel technique for handling the truncation operation is implicit in the proof of this lower bound. In a companion paper, other lower bounds for a large class of problems are proved using a similar technique.
Year
DOI
Venue
1991
10.1145/103516.103522
SFCS '88 Proceedings of the 29th Annual Symposium on Foundations of Computer Science
Keywords
Field
DocType
floor operation,greatest common devisor,lower bound,mod operation,truncation
Integer,Discrete mathematics,Combinatorics,Upper and lower bounds,Omega,Greatest common divisor,Divisor,Computation tree,Mathematics,Computation,Theory of computation
Journal
Volume
Issue
ISSN
38
2
0004-5411
ISBN
Citations 
PageRank 
0-8186-0877-3
16
2.45
References 
Authors
14
3
Name
Order
Citations
PageRank
Yishay Mansour16211745.95
Baruch Schieber22647320.36
Prasoon Tiwari359296.81