Path: utzoo!attcan!utgpu!watmath!maytag!water!wlrush From: wlrush@water.waterloo.edu (Wenchantress Wench Wendall) Newsgroups: ont.events,uw.talks Subject: DATA STRUCTURING SEMINAR Keywords: Mr. Esko Ukkonnen, University of Helsinki will speak on "Efficient Message-ID: <2257@water.waterloo.edu> Date: 19 Apr 89 12:58:04 GMT Distribution: ont Organization: U of Waterloo, Ontario Lines: 35 Approximate String Matching". DEPARTMENT OF COMPUTER SCIENCE UNIVERSITY OF WATERLOO SEMINAR ACTIVITIES DATA STRUCTURING SEMINAR -Monday, April 24, 1989 Mr. Esko Ukonnen of University of Helsinki will speak on "Efficient Approximate String Matching". TIME: 3:30 PM ROOM: DC 1302 ABSTRACT We discuss recent advances in sequential algorithms for computing the edit distance between two strings and for finding approximate occurrences of a string (the pattern) in another string (the text). Such algorithms can be based on a very simple dynamic programming method with running time O(mn) where m and n are the lengths of the two strings compared. The emphasis of the talk is on different ideas of speeding up the basic dynamic programming. The resulting algorithms include a method for the edit distance problem with the desirable property of being the faster the smaller is the actual distance. For the approximate string pattern matching problem we obtain various O(kn) methods where n is the length of the text and k is the maximum distance allowed in a match.