Added:
 - Nondeterministic Z-Automaton [1]
 - ArcFactored Deterministic Z-Automaton [1]
 - ArcFactored Nondeterministic Z-Automaton [1]

[1] Johanna Björklund, Frank Drewes, Giorgio Satta: Z-Automata for
Compact and Direct Representation of Unranked Tree Languages
https://doi.org/10.1007/978-3-030-23679-3_7



Co-authored-by: Tomáš Pecka <tomas.pecka@fit.cvut.cz>

avoid c-arrays

getRank used to return a class that was supposed to be compatible with
unsigned (and size_t) however now it is unsigned by itself

the field has its default value specified, no need for the initializer

... because most developers were copy-pasting the preambule anyway and
did not pay any attention to change it.

Also, I think that git does better job in managing that.

protected field break encapsulation

primitive types don't need std::move

remove unnecessary move of an integral value, add const qualifier to a method
that does not change the this object and remove another use of _identifier

Tomáš Pecka authored 4 years ago and Jan Trávníček committed 4 years ago

Although #pragma once is not a standard, compilers nowadays usually
support it. We don't have any tricky build system so we should be OK.

This also fixes many errors regarding using reserved identifiers (names
starting with double underscore).

The epsilon transitions from the new initial state were labelled with empty,
should be epsilon

I redesigned the algorithm to make it similar to NPDA run implementation, most
importantly to handle cycles, also not even the very basic test that I
introduced didn't pass.

Additionaly, the graphStructuredStacks used to track the pushdown store and output were
incorrectly parametrized with InputSymbolType instead of PushdownStoreSymbolType
and OutputSymbolType.

Also add getTransition from state and transition to state to NPDA.