WILEY-INTERSCIENCE

SERIES IN DISCRETE MATHEMATICS AND OPTIMIZATION

ADVISORY EDITORS

RONALD L. GRAHAM

University of California at San Diego, U.S.A.

JAN KAREL LENSTRA

Department of Mathematics and Computer Science, Eindhoven University of Technology, Eindhoven, The Netherlands

JOEL H. SPENCER

Courant Institute, New York, New York, U.S.A.