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 : firstname.lastname@example.org Output : Valid Input : !email@example.com Output : Not Valid
Below is the implementation:
- Lex program to check if a Date is valid or not
- Lex program to check valid Mobile Number
- Lex Program For checking a valid URL
- Lex Program to accept a valid integer and float value
- Lex program to recognize valid arithmetic expression and identify the identifiers and operators
- YACC program to implement a Calculator and recognize a valid Arithmetic expression
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- Lex program to check whether input number is odd or even
- Lex program to check perfect numbers
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