## Explain Recursive Decent Parsing

A top down parsing that executes a set of recursive procedure to process the input without backtracking is called recursive decent parserThere is a procedure for each non terminal in…

## Algorithm to left factor a grammar

Left factoring is a grammar transformation that is useful for producing a grammar suitable for predictive parsing. Algorithm to left factor a grammar Input: Grammar G Output: An equivalent left factored grammar.For each…

## Algorithm to eliminate left recursion

Algorithm to eliminate left recursionAssign an ordering A1,…,An to the nonterminals of the grammerfor i:=1 to n do beginfor j:=1 to i−1do begin replace each production of the form Ai→Aiɣ by…

## Types of Derivations

There are mainly two types of derivations,Leftmost derivationRightmost derivationLet Consider the grammar with the production S->S+S | S-S | S*S | S/S |(S)| aLeft Most DerivationA derivation of a string…

## Difference between syntax tree and Parse tree

No.Parse TreeSyntax Tree1Interior  nodes are  non-terminals, leaves are terminals.Interior nodes are “operators”, leaves are operands.2Rarely constructed as a data structure.When representing a program in a tree structure usually use a…

## Algorithm to minimizing the number of states of a DFA

Construct an initial partition Π of the set of states with two groups: the accepting states F and the non-accepting states S – FApply the repartition procedure to Π to…

## C program to implement the syntax-directed definition of “if E then S1” and “if E then S1 else S2”

#include #include #include int parsecondition(char[ ],int,char*,int); void gen(char[ ],char[ ],char[ ],int); int main() { int counter=0,stlen=0,elseflag=0; char stmt[60]; char strB[54]; char strS1[50]; char strS2[45]; printf("Format of 'if' statementn example..n"); printf("if(a

## Specification of token

Strings and languages Terms for a part of string Term Definition Prefix of S A string obtained by removing zero or more trailing symbol of string S. e.g., ban is…

## Explain token & pattern and lexemes

Token: Sequence of character having a collective meaning is known as token. Typical tokens are, 1) Identifiers 2) keywords 3) operators 4) special symbols 5) constants Pattern: The set of…

## Role of lexical analysis and its issues

The lexical analyzer is the first phase of compiler. Its main task is to read the input characters and produce as output a sequence of tokens that the parser uses…