Deterministic means that on each input there is one and only one state to which the automata can have the transition from its current state. In deterministic finite automata, the head can move only in one direction to scan the input tape symbols. But in the case of two-way, finite ... Read More

A Regular Expression is a representation of Tokens. But, to recognize a token, it can need a token Recognizer, which is nothing but a Finite Automata (NFA). So, it can convert Regular Expression into NFA.Algorithm for the conversion of Regular Expression to NFAInput − A Regular Expression ROutput − NFA ... Read More

An automata is an abstract model of digital computers with discrete inputs and outputs. Every automata include a mechanism for reading inputs. It is considered that input is a string over a given alphabet, written on an input file that the automata can read. The input file is divided into ... Read More

The language accepted by finite automata can be simply defined by simple expressions known as Regular Expressions. It is an effective approach to describe any language. A regular expression can also be represented as a sequence of patterns that represent a string. Regular expressions are used to connect character sequence ... Read More

Lexical Analysis can be designed using Transition Diagrams.Finite Automata (Transition Diagram) − A Directed Graph or flowchart used to recognize token.The transition Diagram has two parts −States − It is represented by circles.Edges − States are connected by Edges Arrows.Example − Draw Transition Diagram for "if" keyword.To recognize Token ("if"), ... Read More

A compiler is a computer program that converts source code written in a computer language (the source language) into another computer language (the target language, providing having a binary form referred to as object code). The best reason for inadequate to convert source code is to create an executable code.The ... Read More

It is an approach for making a self-compiling compiler that is a compiler written in the source programming language that it determine to compile. A bootstrap compiler can compile the compiler and thus you can use this compiled compiler to compile everything else and the future versions of itself.Uses of ... Read More

Macro-ProcessorsMany assembly languages support a “macro” facility whereby a macro statement will translate into a sequence of assembly language statements and possibly other macro statements before being translated into a machine program. Therefore, a macro facility is a text replacement capability.It can illustrate the utility of macros, consider a situation ... Read More

Detection and reporting of errors in the source program is the main function of the compiler. An error can occur at any phase of compilation. A good compiler must determine the line number of the program exactly, where the errors have occurred. Various errors that can occur at a different ... Read More

Imperative LanguagesImperative languages are those which facilitate the computation by mean of state changes. By a state, it means the condition of a computer’s random access memory (RAM) or storage. It is helpful to think of computer memory as a sequence of snapshots, each one capturing the values in all ... Read More