UVa 00232 - Crossword Answers (complex array manipulation problem)

Link: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=4&page=show_problem&problem=168
Sol:

import java.util.Scanner;
	import java.io.*;
	/* The hardest part of this problem was to read input with Java */
	/* This will only work with ANSI encoded files used for input */
	class Item {
	public char c;
	public int number;
	Item() {
	this.c = '-';
	this.number = -1;
	}
	}
	class Board {
	public int m, n;
	Item map[][];
	public Board(int m, int n) {
	this.m = m;
	this.n = n;
	map = new Item[m][n];
	for (int i = 0; i < m; i++)
	for (int j = 0; j < n; j++)
	map[i][j] = new Item();
	}
	public Item getItem(int x, int y) {
	return map[x][y];
	}
	public void setItem(int x, int y, char item) {
	map[x][y].c = item;
	}
	private boolean isOnTheBoard(int i, int j) {
	return i >= 0 && j >= 0 && i < m && j < n;
	}
	@Override
	public String toString() {
	StringBuilder builder = new StringBuilder();
	for (int i = 0; i < m; i++) {
	for (int j = 0; j < n; j++) {
	builder.append("[" + map[i][j].c + "," + map[i][j].number + "]");
	}
	builder.append("\n");
	}
	return builder.toString();
	}
	public void doTheCalculation() {
	calculateEligible();
	System.out.println("Across");
	calculateWords(0, 1);
	System.out.println("Down");
	calculateWords(1, 0);
	}
	private void calculateEligible() {
	int count = 1;
	for (int i = 0; i < m; i++) {
	for (int j = 0; j < n; j++) {
	if (map[i][j].c != '*'
	&& (!isOnTheBoard(i-1, j)
	|| !isOnTheBoard(i, j-1)
	|| map[i-1][j].c == '*'
	|| map[i][j-1].c == '*')) {
	map[i][j].number = count++;
	}
	}
	}
	}
	private void calculateWords(int x, int y) {
	for (int i = 0; i < m; i++) {
	for (int j = 0; j < n; j++) {
	if (map[i][j].number != -1) {
	if (!isOnTheBoard(i - x, j - y) || map[i - x][j - y].c == '*') {
	printWord(i, j, x, y);
	}
	}
	}
	}
	}
	private void printWord(int i, int j, int x, int y) {
	StringBuilder builder = new StringBuilder();
	int ni, nj;
	for (int k = 0; k < 10; k++) {
	ni = i + x * k;
	nj = j + y * k;
	if (!isOnTheBoard(ni, nj) || map[ni][nj].c == '*')
	break;
	builder.append(map[ni][nj].c);
	}
	System.out.printf("%3d.%s\n",map[i][j].number, builder.toString());
	}
	}
	public class Main {
	public static void main(String[] args) throws Exception {
	Scanner in = new Scanner(System.in);
	String line;
	int tc = 0, m, n;
	while (true) {
	m = in.nextInt();
	if (m == 0)
	break;
	n = in.nextInt();
	in.nextLine();
	if (++tc != 1) {
	System.out.println();
	}
	Board board = new Board(m, n);
	for (int i = 0; i < m; i++) {
	line = in.nextLine();
	for (int j = 0; j < n; j++) {
	board.setItem(i, j, line.charAt(j));
	}
	}
	System.out.println("puzzle #" + tc + ":");
	board.doTheCalculation();
	}
	}
	}