Durak is a Russian card game in which players try to get rid of all their cards via a particular attack/defense mechanism. The last player standing with cards loses. We show that, even restricted to the perfect information two-player game, finding optimal moves is a hard problem. More precisely, we prove that, given a generalized durak position, it is PSPACE-complete to decide if a player has a...

In general, computation of graph vulnerability parameters is NP-complete. In past, some algorithms were introduced to prove that computation of toughness, scattering number, integrity and weighted integrity parameters of interval graphs are polynomial. In this paper, two different vulnerability parameters of graphs, tenacity and rupture degree are defined. In general, computing the tenacity o...

Absolute differential cross sections for electron-impact excitation of Rydberg states of CO have been measured from threshold to 3.7 eV above threshold and for scattering angles between 20◦ and 140◦. Measured excitation functions for the b 36+, B 16+ and E 15 states are compared with cross sections calculated by the Schwinger multichannel method. The behaviour of the excitation functions for th...

Peg solitaire is a single-player board game. The goal of the game to remove all but one peg from board. on graphs played arbitrary graphs. A graph called solvable if there exists some vertex s such that it possible starting with as initial hole. In this paper, we prove NP-complete decide or not.

The disjointness of a stabilizer code is quantity used to constrain the level logical Clifford hierarchy attainable by transversal gates and constant-depth quantum circuits. We show that for any positive integer constant $c$, problem calculating $c$-disjointness, or even approximating it within multiplicative factor, NP-complete. provide bounds on various families, including Calderbank-Shor-Ste...