# Lex and Yacc

## Lex Program to recognize and count the number of keywords

Lex Program to recognize and count the number of keywords in a given input file Problem definition: Write a Lex program to recognize the keywords in a given input file, count them, and display the result on standard output. Structure of LEX Program: %{Definition section%} %% Rules section %% User Subroutine section   Click here […]

## Lex program to identify the capital words from string

Lex program to identify the capital words from the given input string Problem definition: Write a Lex Program to recognize the capital words from the given input string and display the result on standard output. Video Tutorial: Structure of LEX Program: %{Definition section%} %% Rules section %% User Subroutine section   Click here to learn

## Lex program to count number of vowels & consonants

Lex program to count the number of vowels & consonants from the given input string. Problem definition: Write a Lex Program to recognize vowels and consonants in a given string and count them and display the result on standard output. Structure of LEX Program: %{Definition section%} %% Rules section %% User Subroutine section   Click

## Lex Program to simple or compound sentence

Lex Program to recognize whether a given sentence is simple or compound Problem definition: Write a Lex Program to recognize whether a given sentence is a simple or compound sentence. Print the result on standard output. A simple sentence is one that does not contain another sentence as a component. These sentences are represented by

## Lex Program to recognize a valid arithmetic expression

Lex program to recognize a valid arithmetic expression and to recognize the identifiers and operators present. Print them separately. Problem definition: Write a Lex Program to recognize a valid arithmetic expression. If the arithmetic expression is valid then recognize the identifiers and operators present in the expression and print identifiers and operators separately. Structure of

## Lex program to count the number of comment lines in C program

Lex program to count the number of comment lines in a given C program and eliminate the comments and write into the output file Problem definition: Write a lex code to count the number of comment lines in a given C program. Also, eliminate them and copy the resulting program into a separate file. Structure

## Lex Program to count numbers of lines, words, spaces and characters

Lex Program to count the numbers of lines, words, spaces, and characters in a given statement Problem definition: Write a lex program to recognize lines, words, spaces, and characters in a given statement and display the numbers of lines, words, spaces, and characters on standard output. Structure of LEX Program: %{Definition section%} %% Rules section

## Lex Program to recognize comments, numbers, identifiers, and strings

Lex Program to recognize and display comments, numbers, identifiers, and strings in a given statement Problem definition: Write a lex program to recognize comments, numbers, identifiers, and strings in a given statement and display them on standard output. Structure of LEX Program: %{Definition section%} %% Rules section %% User Subroutine section   Click here to

## Regular Expressions LEX and YACC

Regular Expressions in LEX and YACC In this article, we will discuss the concept of Regular Expressions LEX and YACC and different LEX actions used while writing LEX programs. Definition of Regular Expressions: A Regular Expression is a pattern description using a “meta” language, a language that you use to describe particular patterns of interest.

## Parser-Lexer Communication

Parser-Lexer Communication – LEX and YACC In this article, we will understand how Parser-Lexer (Syntax Analyzer and Lexical Analyzer) Communicates with each other. Introduction to LEX: Lex & YACC are the tools designed for writers of compilers & interpreters. Lex & Yacc helps us write programs that transform structured input. In programs with structured input,