Automata Programs:

This document explains how to compile and run the following programs:

1. Lexical Analyzer in C
2. Lexical Analyzer using Lex Tool
3. YACC Specifications for Syntactic Categories
4. Find ε-Closure of all states in an NFA
5. Convert NFA with ε-transition to NFA without ε-transition
6. Convert NFA to DFA
7. Minimize a DFA

Prerequisites

• GCC compiler installed
• Basic knowledge of terminal commands

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1. Running the Lexical Analyzer Program in C

Steps to Compile and Run:

gcc lexical_analyzer.c -o lexical_analyzer
./lexical_analyzer

Input Format:

• Enter a C program as input.
• Press Ctrl+D (Linux/Mac) or Ctrl+Z (Windows) to end input.

Example Input:

int main() {
    int a = 10;
    float b = 5.5;
    if (a > b) {
        printf("Hello World\n");
    }
    return 0;
}

Expected Output:

int is a keyword
main is an identifier
( is a special symbol
) is a special symbol
{ is a special symbol
int is a keyword
a is an identifier
10 is a number
; is a special symbol
float is a keyword
b is an identifier
5.5 is a number
; is a special symbol
if is a keyword
( is a special symbol
a is an identifier
> is a special symbol
b is an identifier
) is a special symbol
{ is a special symbol
printf is an identifier
( is a special symbol
"Hello World\n" is a string
) is a special symbol
; is a special symbol
} is a special symbol
return is a keyword
0 is a number
; is a special symbol
} is a special symbol
Total number of lines: 9

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2. Running the Lexical Analyzer using Lex Tool

Lex Program (lexical_analyzer.l):

%{
#include <stdio.h>
%}

DIGIT [0-9]+
ID [a-zA-Z_][a-zA-Z0-9_]*
WHITESPACE [ \t\n]+

%%
{DIGIT}     { printf("%s is a number\n", yytext); }
{ID}        { printf("%s is an identifier\n", yytext); }
[+\-*/=;]   { printf("%s is an operator or special symbol\n", yytext); }
{WHITESPACE} { /* Ignore whitespace */ }
.           { printf("%s is an unknown character\n", yytext); }
%%

int yywrap() {
    return 1;
}

int main() {
    yylex();
    return 0;
}

Steps to Compile and Run:

lex lexical_analyzer.l
gcc lex.yy.c -o lexical_analyzer -ll
./lexical_analyzer

---

3. Running the YACC Specification Programs

Steps to Compile and Run:

yacc -d arith.y
lex arith.l
gcc y.tab.c lex.yy.c -o arith -ll
./arith

Example Implementations:

• Recognizing valid arithmetic expressions (arith.y, arith.l)
• Recognizing valid variable names (var.y, var.l)
• Calculator implementation using Lex and YACC (calc.y, calc.l)
• Abstract syntax tree generation (ast.y, ast.l)

---

4. Running the ε-Closure Program

Steps to Compile and Run:

gcc epsilon_closure.c -o epsilon_closure
./epsilon_closure

Example Input:

11
8
0 1
1 2
1 3
6 1
0 7
4 6
5 6
6 7

Example Output:

ε-Closure of states:
ε-Closure(q0): { q0 q1 q2 q3 q7 }
ε-Closure(q1): { q1 q2 q3 }
ε-Closure(q2): { q2 }
ε-Closure(q3): { q3 }
ε-Closure(q4): { q1 q2 q3 q4 q6 q7 }
ε-Closure(q5): { q1 q2 q3 q5 q6 q7 }
ε-Closure(q6): { q1 q2 q3 q6 q7 }
ε-Closure(q7): { q7 }
ε-Closure(q8): { q8 }
ε-Closure(q9): { q9 }
ε-Closure(q10): { q10 }

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5. Running the NFA-ε to NFA Program

Steps to Compile and Run:

gcc nfa_epsilon_to_nfa.c -o nfa_epsilon_to_nfa
./nfa_epsilon_to_nfa

Example Output:

NFA after removing ε-transitions:
δ(q0, a) -> { q1 }
δ(q0, b) -> { q2 }
δ(q1, a) -> { }
δ(q1, b) -> { q2 }

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6. Running the NFA to DFA Conversion Program

Steps to Compile and Run:

gcc nfa_to_dfa.c -o nfa_to_dfa
./nfa_to_dfa

Example Output:

DFA Transition Table:
δ(q0, a) -> q1
δ(q0, b) -> q2
δ(q1, a) -> {}
δ(q1, b) -> q2

---

7. Running the DFA Minimization Program

Steps to Compile and Run:

gcc minimize_dfa.c -o minimize_dfa
./minimize_dfa

Example Output:

Minimized DFA Table:
q0 -> { q1, q2 }
q1 -> { q2, q3 }

This guide provides the steps to run each automata conversion program. Modify the input values as needed to test different cases!