SolutionStep1 − First of all, convert it into augmented grammar G′ and number the productions(0) S′ → S(1) S → L = R(2) S → R(3) L →∗ R(4) L → id(5) R → LStep2 − Find closure and goto function to construct LR (0) items.In the following set of ... Read More

SLR ParserSLR represents "Simple LR Parser". It is very easy and cost-effective to execute. The SLR parsing action and goto function from the deterministic finite automata that recognizes viable prefixes. It will not make specificially defined parsing action tables for all grammars but does succeed on several grammars for programming ... Read More

A parser is the second phase of compilation. The parser takes as its input tokens generated from the previous phase, i.e., the Lexical Analyzer phase, and groups them in such a way that their syntax can be recognized.For example, Consider I0I0 − E′ → ∙ E      E → ... Read More

SolutionSteps to produce SLR Parsing TableGenerate Canonical set of LR (0) itemsCompute FOLLOW as required by Rule (2b) of Parsing Table Algorithm.Computation of FOLLOWBy Rule (1) of FOLLOWFOLLOW(E) = {$}                                         ... Read More

SLR represents "Simple LR Parser". It is very simple and economical to execute. But it fails to make a parsing table for some class of grammars, i.e., why CLR and LALR are used which implements mainly all class or type of grammars. It constructs parsing tables which helps to perform ... Read More

SolutionStep1− Construct the Augmented Grammar and number the productions(0) E′ → E(1) E → E + T(2) E → T(3) T → T * F(4) T → F(5) F → (E)(6) F → idStep2− Apply closure to the set of items & find gotoSquare Boxes represent the new states or ... Read More

SolutionComputation of FIRSTS → L = R∵ L does not derive ε. By rule (4b)of FIRST∴ FIRST(S) = {FIRST(L)}                                                  (1)S → R∵ R does not derive ... Read More

The LR (0) item for Grammar G consists of a production in which symbol dot (.) is inserted at some position in R.H.S of production.For Example − For the production S → ABC, the generated LR (0) items will be −S →∙ ABCS → A ∙ BCS → AB ∙ ... Read More

LR Parser is a class of Bottom-Up Parser that is used to parse Context-Free Grammars. LR Parsing is known as LR (K) parsing whereL represents Left to Right Scanning of InputR represents Rightmost DerivationK is the number of input symbols of Look ahead that are used in developing parsing decisions.LR ... Read More

Top-Down Parsing with BacktrackingIn Top-Down Parsing with Backtracking, Parser will attempt multiple rules or production to discover the match for input string by backtracking at every step of derivation. So, if the used production does not give the input string as needed, or it does not match with the needed ... Read More