We show that computing the lexicographically first four-coloring for planar graphs is p 2hard. This result optimally improves upon a result of Khuller and Vazirani who prove this ...
We present explicit solutions of a class of recurrences related to the Quickselect algorithm. Thus we are immediately able to solve recurrences arising at the partial sorting probl...
We consider a special subgraph of a weighted directed graph: one comprising only the k heaviest edges incoming to each vertex. We show that the maximum weight branching in this su...
We investigate determining the exact bounds of the frequencies of conjunctions based on frequent sets. Our scenario is an important special case of some general probabilistic logi...
In this paper, we strengthen two recent undecidability results of [9,10] about weighted timed automata, an extension of timed automata with cost variables. More precisely, we prop...
Counting the number of distinct factors in the words of a language gives a measure of complexity for that language similar to the factor-complexity of infinite words. Similarly as ...
Knuth-Bendix completions of the equational theories of k 2 commuting group endomorphisms are obtained, using automated theorem proving and modern termination checking. This impro...