import java.util.NoSuchElementException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;



/**
 * Does parsing of simple expressions.
 * This version has only a main program; you have to provide the rest.
 */
 
 class Parser {
 
 	/* 
 	 * You will need to create fields and methods here.  The fields
 	 * are used to maintain the current state of the parser.  Useful
 	 * fields might include the current expression being parsed, the
 	 * ExpressionTokenizer, and the current values of x and y.
 	 * You need to create a constructor, and methods for
 	 * expression, term, and factor.  You may find it useful to create
 	 * additional methods and fields.
 	 */
 	 
 
 	 /**
	  * Main program reads expressions, one per line, and evaluates
	  * them.  Takes a single command-line arg specifying the
	  * size of the matrix on which the expression is evaluated.
	  */
	 public static void main (String[] arg) {
	 	
	 	int size = 1;			// Size of the output matrix
	 	String expression;		// Input expression
	 	Parser parser;			// The parser/evaluator
	 	
	 	// Look for a command line argument
	 	if (arg.length != 1) {
	 		System.out.println("Need a command line argument.");
	 		System.out.println("In CodeWarrior, select 'Java Application Settings...' in the Edit menu.");
	 		System.out.println("Place your argument in the 'Parameters' box.");
	 		throw new IllegalArgumentException();
	 		}
	 		
	 	// Determine the size of the output matrix
	 	try {
	 		size = Integer.parseInt(arg[0]);
	 		}
	 	catch (NumberFormatException e) {
	 		System.out.println("Bad number on command line.");
	 		throw new IllegalArgumentException();
	 		}
	 	
	 	// Prepare the standard input for reading lines
	 	BufferedReader in = 
			new BufferedReader(new InputStreamReader(System.in));
			
		// Read expressions, one per line, until an empty line is read
		while (true) {
			try {
				System.out.print("Input: ");
				expression = in.readLine();
				if (expression.equals("")) break;
				
				parser = new Parser(expression);
				
				// Print the output in matrix form
				for (int j = 0; j < size; j++) {
					for (int i = 0; i < size; i++) {
						System.out.print(parser.evaluate(i,j) + " ");
						}
					System.out.println();
					}
				}
				
			// This exception occurs if you read past end-of-line
			catch (NoSuchElementException e) {
				System.out.println("Read past end-of-file");
				}
				
			// This exception occurs when a failed attempt is made to
			// convert a String into a Double using Double.valueOf()
			catch (NumberFormatException e) {
				System.out.println("Badly formed number");
				}
				
			// This exception should occur if something goes wrong
			// while parsing; the message should be helpful.
			catch (IllegalArgumentException e) {
				System.out.println(e.getMessage());
				}
				
			// This shouldn't occur, but is required when reading
			// from a file.
			catch (IOException e) {
				System.out.println("Unknown IO problem.");
				}
			}
		}
	}