README.md

Cycle 3 — p12: FIRST and FOLLOW Sets Calculator

Files:

• p12.c - Implementation of FIRST and FOLLOW sets computation

Brief description:

This program computes FIRST and FOLLOW sets for a context-free grammar, which are essential for parser construction. Features:

1. FIRST Set Computation:

   • Handles all types of productions including ε-productions
   • Recursively computes FIRST for non-terminals
   • Properly handles cases where FIRST of multiple symbols needed
   • Maintains visited flags to handle recursive definitions

2. FOLLOW Set Computation:

   • Implements all FOLLOW set rules including:
     • $ for start symbol
     • FIRST of next symbol (excluding ε)
     • FOLLOW of left-hand side when needed
   • Handles recursive FOLLOW dependencies
   • Properly propagates FOLLOW sets in all cases

3. Input/Output:

   • Takes grammar productions as input
   • Shows complete FIRST and FOLLOW sets for all non-terminals
   • Uses uppercase letters for non-terminals
   • Handles all special cases properly

Usage: Enter the number of productions and then enter each production in the format A=BC or similar.