Lex is a computer program that generates lexical analyzers. Lex reads an input stream specifying the lexical analyzer and outputs source code implementing the lexer in the C programming language.
The commands for executing the lex program are:
lex abc.l (abc is the file name) cc lex.yy.c -efl ./a.out
Let’s see lex program to check valid email.
Input : email@example.com Output : Valid Input : !firstname.lastname@example.org Output : Not Valid
Below is the implementation:
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