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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- 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
- Lex program to check whether the input is digit or not
- Lex program to check whether a given number is even or odd
- Lex program to check whether input number is odd or even
- Lex program to check perfect numbers
- Lex program to check whether an year is a leap year or not
- Lex Program to check whether a number is Prime or Not
- Lex program to check whether given string is Palindrome or Not
- Lex program to check whether given number is armstrong number or not
- Lex Program to remove comments from C program
- LEX program to add line numbers to a given file
- Lex Program to Identify and Count Positive and Negative Numbers
- Lex Program to count number of words
- Lex program to take input from file and remove multiple spaces, lines and tabs
- Lex program to count the number of lines, spaces and tabs
- Lex program to identify the identifier
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