package HW3;

import java.util.*;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.StreamTokenizer;
import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;

public class first {

	private static final String FILE1 = "src/G1.txt";
	private static final String FILE2 = "src/G2.txt";
	private static ArrayList<Rule> rules = new ArrayList<Rule>();

	public static void main(String[] args) throws FileNotFoundException {

		File file = new File(FILE1);
		Scanner in = new Scanner(file);

		int cur = 0;
		Symbol tempTerm = new Symbol("", false);
		ArrayList<Symbol> tempOrder = new ArrayList<Symbol>();

		while(in.hasNextLine()) {
			String nextLine = in.nextLine();
			if(nextLine.equals("$")) {
				rules.add(new Rule(tempTerm, tempOrder));
				cur = 0;
			} else if(cur == 0) {
				tempOrder = new ArrayList<Symbol>();
				tempTerm = new Symbol(nextLine, isTerminalSymbol(nextLine));
				cur++;
			} else {
				tempOrder.add(new Symbol(nextLine, isTerminalSymbol(nextLine)));
			}
		}

		System.out.println(rules.get(2).getNTS());


		for(int i = 0; i < rules.size(); i++) {
			System.out.print(rules.get(i).getNTS() + " = {" );
			findFirst(rules.get(i));
			System.out.print("}");
			System.out.println(" ");
		}

	}

	public static void findFirst(Rule rule) {
		ArrayList<Symbol> ord = rule.getOrder();
		Symbol firstSymbol = ord.get(0);
		if(firstSymbol.isTerminal()) {
			System.out.print(" " + firstSymbol.getTerm() + " ");
		} else {
			for(int i = 0; i < rules.size(); i++) {
				if(firstSymbol.getTerm().equalsIgnoreCase(rules.get(i).getNTS())) {
					if(rule.getNTS().equalsIgnoreCase(rules.get(i).getNTS())) {
						continue;
					}
					findFirst(rules.get(i));
				}
			}
		}
	}

	public static boolean isTerminalSymbol(String s) {
		return !Character.isUpperCase(s.toCharArray()[0]);
	}
}

class Rule {
	Symbol term;
	ArrayList<Symbol> order;
	public Rule(Symbol term, ArrayList<Symbol> order) {
		this.term = term;
		this.order = order;
	}
	public String getNTS() {
		return term.getTerm();
	}
	public ArrayList<Symbol> getOrder() {
		return order;
	}
}

class Symbol {
	String term;
	boolean terminal;
	public Symbol(String term, boolean terminal) {
		this.term = term;
		this.terminal = terminal;
	}
	public boolean isTerminal() {
		return terminal;
	}
	public String getTerm() {
		return term;
	}
}