Lex and YACC Programs Repository

This repository contains 12 programs written using Lex and YACC, labeled as 1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b, 5, 6, 7, and 8. Each program demonstrates specific functionalities and parsing tasks, with some involving both Lex and YACC.

Getting Started

Prerequisites

To build and run the programs, ensure you have the following tools installed:

• lex (or flex)
• yacc (or bison)
• A C compiler (e.g., gcc)

Building and Running

For each program:

1. Navigate to the respective directory (e.g., cd 1a).

2. Run the following commands:

   For Lex files:

   lex <filename>.l
   gcc lex.yy.c -o <output>
   ./<output>

   For YACC files:

   yacc -d <filename>.y
   lex <corresponding Lex file>.l
   gcc y.tab.c lex.yy.c -o <output>
   ./<output>

Overview of Programs

Program 1a

• 1a.l: Counts the number of words, lines, characters, and whitespaces in the input.

Program 1b

• 1b.l & 1b.y: Validates input strings based on defined grammar rules.

Program 2a

• 2a.l: Counts positive/negative integers and fractions from the input.

Program 2b

• 2b.l & 2b.y: Evaluates arithmetic expressions.

Program 3a

• 3a.l: Removes comments from a C program and counts the total number of comments.
• Input (3a_ip.txt): A C program with single-line and multi-line comments.
• Output (3a_op.txt): The same program with all comments removed.

Program 3b

• 3b.l & 3b.y: Parses and validates nested for loops and counts them.

Program 4a

• 4a.l: Processes arithmetic expressions in a C-style code snippet.
  • Counts keywords (int, float, char), identifiers, and operators.
• Input (4a_ip.txt): C code snippet with declarations and arithmetic operations.

Program 4b

• 4b.l & 4b.y: Parses and validates nested if statements and counts them.

Program 5

• 5.l & 5.y: Tokenizes type declarations, identifiers, and arrays, and parses declarations to count total variables.
• Input (5_input.txt): Sample type declarations with variables and arrays.

Program 6

• 6.l & 6.y: Tokenizes mathematical expressions with variables and numbers, and generates three-address code and quadruple code for expressions.

Program 7

• 7.l & 7.y: Tokenizes components of a C program, ignoring comments, and parses and validates the structure of C programs, including functions and statements.
• Input (7_input.txt): A sample C program demonstrating declarations, statements, and comments.

Program 8

• 8.l & 8.y: Tokenizes components for assembly-like code generation and generates assembly-like code for simple C programs with arithmetic and printf statements.

Contributing

Feel free to contribute by opening issues or submitting pull requests to enhance the repository.

License

This project is open-source and available under the MIT License.