Lex is a computer program that generates lexical analyzers and was written by Mike Lesk and Eric Schmidt.
Lex reads an input stream specifying the lexical analyzer and outputs source code implementing the lexer in the C programming language.
Prerequisite: Flex (Fast lexical Analyzer Generator)
Input: Hello everyone Output: 2 Input: This is GeeksforGeeks Output: 3
Note: The words can consist of lowercase characters, uppercase characters and digits.
Below is the implementation to count the number of words.
- Lex program to count words that are less than 10 and greater than 5
- Lex program to count the number of lines, spaces and tabs
- LEX program to count the number of vowels and consonants in a given string
- Lex program to check whether given number is armstrong number or not
- Lex Program to Identify and Count Positive and Negative Numbers
- Lex program to Count the Positive numbers, Negative numbers and Fractions
- Lex program to count the frequency of the given word in a file
- Lex Program to remove comments from C program
- Lex code to count total number of tokens
- 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 whether a number is Prime or Not
- Lex program to check valid Mobile Number
- DFA in LEX code which accepts even number of zeros and even number of ones
- DFA in LEX code which accepts Odd number of 0’s and even number of 1’s
- LEX program to add line numbers to a given file
- Lex Program For checking a valid URL
- Lex program to take input from file and remove multiple spaces, lines and tabs
- Lex program to identify the identifier
- Lex Program to accept a valid integer and float value
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