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 vowels and consonants in a given string
- Lex program to count the number of lines, spaces and tabs
- Lex program to count the frequency of the given word in a file
- Lex Program to Identify and Count Positive and Negative Numbers
- Lex program to check whether given number is armstrong number or not
- Lex code to count total number of tokens
- Lex program to Count the Positive numbers, Negative numbers and Fractions
- Program for nth Catalan Number
- 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
- Lex Program to remove comments from C program
- DFA in LEX code which accepts even number of zeros and even number of ones
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