Theory: Difference between revisions

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* Rewrite rule: αAβ→αγβ, where A is a non-terminal, and {α, β, γ} are strings of terminals and non-terminals
* Rewrite rule: αAβ→αγβ, where A is a non-terminal, and {α, β, γ} are strings of terminals and non-terminals
* Recognized by linear bounded automata
* Recognized by linear bounded automata
===Recursive Languages (Class [http://qwiki.stanford.edu/wiki/Complexity_Zoo:R#r R])===
* Decided by [[Turing Machines]]
===Recursively-Enumerable Languages (Class [http://qwiki.stanford.edu/wiki/Complexity_Zoo:R#re RE])===
===Recursively-Enumerable Languages (Class [http://qwiki.stanford.edu/wiki/Complexity_Zoo:R#re RE])===
* Type 0 of the [[Chomsky Hierarchy]], and a proper superset of CSLs
* Type 0 of the [[Chomsky Hierarchy]], and a proper superset of CSLs
* Rewrite rule: α→β, where {α, β} are strings of terminals and non-terminals
* Rewrite rule: α→β, where {α, β} are strings of terminals and non-terminals
* Recognized by [[Turing Machines]] (ie, any 'yes' answer can be verified, but 'no' cases might not halt)
* Recognized **but not decided** by [[Turing Machines]] (ie, any 'yes' answer can be verified, but 'no' cases might not halt)
===Recursive Languages (Class [http://qwiki.stanford.edu/wiki/Complexity_Zoo:R#r R])===
 
* Decided by [[Turing Machines]]
[[Category: CS GRE Prep]]
[[Category: CS GRE Prep]]