Context-Free Grammars (CFGs) and Parsing Expression Grammars (PEGs) have several similarities and a few differences in both their syntax and semantics, but they are usually presented through formalisms that hinder a proper comparison. In this paper we present a new formalism for CFGs that highlights the similarities and differences between them. The new formalism borrows from PEGs the use of pa...

The AB game is a two-player game, where the codemaker has to choose a secret code and the codebreaker has to guess it in as few questions as possible. It is a variant of the famous Mastermind game, with the only difference that all pegs in both, the secret and the questions must have distinct colors. In this work, we consider the Generalized AB game, where for given arbitrary numbers p, c with ...

Hydrogels, networks of cross-linked hydrophilic polymers, are an important class of soft materials with many of their properties similar to those of biological tissues. While these macroscopic materials have been intensively studied and exploited in various technological areas, their nanosized counterparts, the so-called nanogels, are currently attracting significant attention for their potenti...

The article presents the results of increasing efficiency cleaning raw cotton based on use improving design unit. In zone from small weeds, a peg drum with different diameters pegs was used. Experimental studies have determined optimal value pegs.

The intestinal mucosa plays a fundamental role as the site for absorption of nutrients, and as an important barrier from potentially harmful agents in the intestinal lumen. Little is known of the permeability properties of the intestinal mucosa in uraemic patients. The intestinal permeability to differently sized polyethylene glycols (PEGs; range 326-1254 daltons) was studied in nine patients w...

Fixation of the glenoid component is critical to the outcome of total shoulder arthroplasty. In an in vitro study, we analysed the effect of surface design and thickness of the cement mantle on the pull-out strength of the polyethylene pegs which are considered essential for fixation of cemented glenoid components. The macrostructure and surface of the pegs and the thickness of the cement mantl...

Parsing Expression Grammars (PEGs) are a formalism that can describe all deterministic context-free languages through a set of rules that specify a top-down parser for some language. PEGs are easy to use, and there are efficient implementations of PEG libraries in several programming languages. A frequently missed feature of PEGs is left recursion, which is commonly used in Context-Free Grammar...

Grammar-based sentence generation has been thoroughly explored for Context-Free Grammars (CFGs), but remains unsolved for recognition-based approaches such as Parsing Expression Grammars (PEGs). Lacking tool support, language designers using PEGs have difficulty predicting the behaviour of their parsers. In this paper, we extend the idea of derivatives, originally formulated for regular express...

The generalized Tower of Hanoi problem with h ≥ 4 pegs is known to require a sub-exponentially fast growing number of moves in order to transfer a pile of n disks from one peg to another. In this paper we study the Pathh variant, where the pegs are placed along a line, and disks can be moved from a peg to its nearest neighbor(s) only. Whereas in the simple variant there are h(h−1)/2 possible bi...

Parsing Expression Grammars (PEGs) are a new formalism to describe a top-down parser of a language. However, error handling techniques that are often applied to top-down parsers are not directly applicable to PEGs. This problem is usually solved in PEGs using a heuristic that helps to simulate the error reporting technique from topdown parsers, but the error messages are generic. We propose the...