Investigation of languages including stochastic ones that are parsed in a linear or quadratic time resulted in these papers:

• Annotated regular expressions and input-driven languages,
• Input-driven regular expressions (vision paper),
• One-Counter Automata for Parsing and Language Approximation,
• The Viterbi algorithm for subsets of stochastic context-free languages,
• Data parsing using tier grammars.

See also tutorial Finite State Machines.
 

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