FLEX (Fast Lexical Analyzer Generator) is a tool/computer program for generating lexical analyzers (scanners or lexers) written by Vern Paxson in C around 1987. Lex reads an input stream specifying the lexical analyzer and outputs source code implementing the lexer in the C programming language. The function yylex() is the main flex function which runs the Rule Section.
Prerequisite: FLEX (Fast Lexical Analyzer Generator)
Input: hello how are you? Output: hellohowareyou? Input: Welcome to Geeks for Geeks Output: WelcometoGeeksforGeeks
Open input file in read mode and whenever parser encounters newline (\n), space ( ) or tab (\t) remove it and write all the other characters in output file.
Input File: Input.txt (Input File used in this program)
Below is the implementation program:
- Lex Program to print the total characters, white spaces, tabs in the given input file
- Lex program to count the number of lines, spaces and tabs
- C Program to count number of lines in a file
- Input an integer array without spaces in C
- Implement your own tail (Read last n lines of a huge file)
- How to use getline() in C++ when there are blank lines in input?
- C program to copy contents of one file to another file
- Program to print last 10 lines
- C program to delete a file
- Lex program to search a word in a file
- LEX program to add line numbers to a given file
- C Program to print contents of file
- C Program to find size of a File
- Lex Program to remove comments from C program
- C Program to merge contents of two files into a third file
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