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import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.ArrayList;
public class day11 {
public static void main(String args[]) throws IOException {
RandomAccessFile input = new RandomAccessFile("input", "r");
System.out.println("Day 11 Part 1: " + part1(input));
input.seek(0);
System.out.println("Day 11 Part 2: " + part2(input));
input.close();
}
public static String part1(RandomAccessFile input) throws IOException {
ArrayList<ArrayList<Pixel>> image = new ArrayList<>();
String line;
while ((line = input.readLine()) != null) {
ArrayList<Pixel> linea = new ArrayList<>();
for (char ch: line.toCharArray()) {
if (ch == '.') {
linea.add(Pixel.Space);
} else if (ch == '#') {
linea.add(Pixel.Galaxy);
}
}
image.add(linea);
}
for (int i = image.size() - 1; i >= 0; i--) {
if (allSpace(image.get(i))) {
image.add(i+1, (ArrayList<Pixel>) image.get(i).clone());
}
}
for (int i = image.get(0).size() - 1; i >= 0; i--) {
ArrayList<Pixel> col = new ArrayList<>();
for (ArrayList<Pixel> row: image) {
col.add(row.get(i));
}
if (allSpace(col)) {
for (ArrayList<Pixel> row: image) {
row.add(i+1, row.get(i));
}
}
}
ArrayList<Integer[]> galaxies = new ArrayList<>();
for (int r = 0; r < image.size(); r++) {
for (int c = 0; c < image.get(0).size(); c++) {
if (image.get(r).get(c) == Pixel.Galaxy) {
galaxies.add(new Integer[] {r, c});
}
}
}
int sum = 0;
for (int i = 0; i < galaxies.size() - 1; i++) {
for (int j = i + 1; j < galaxies.size(); j++) {
sum += dist(galaxies.get(i), galaxies.get(j));
}
}
return Integer.toString(sum);
}
public static String part2(RandomAccessFile input) throws IOException {
ArrayList<Integer[]> galaxies = new ArrayList<>();
String line;
int h = 0;
int w = 0;
while ((line = input.readLine()) != null) {
w = 0;
for (char ch: line.toCharArray()) {
if (ch == '#') {
galaxies.add(new Integer[] {h, w});
}
w += 1;
}
h += 1;
}
for (int r = h - 1; r >= 0; r--) {
if (rowEmpty(galaxies, r)) {
moveDown(galaxies, r, 999999);
}
}
for (int c = w - 1; c >= 0; c--) {
if (colEmpty(galaxies, c)) {
moveRight(galaxies, c, 999999);
}
}
long sum = 0;
for (int i = 0; i < galaxies.size() - 1; i++) {
for (int j = i + 1; j < galaxies.size(); j++) {
sum += longDist(galaxies.get(i), galaxies.get(j));
}
}
return Long.toString(sum);
}
static enum Pixel {
Space,
Galaxy
}
private static boolean allSpace(ArrayList<Pixel> line) {
for (Pixel px: line) {
if (px == Pixel.Galaxy) {
return false;
}
}
return true;
}
private static int dist(Integer[] i, Integer[] j) {
return Math.abs(i[0] - j[0]) + Math.abs(i[1] - j[1]);
}
private static long longDist(Integer[] i, Integer[] j) {
return Math.abs(i[0] - j[0]) + Math.abs(i[1] - j[1]);
}
private static boolean rowEmpty(ArrayList<Integer[]> galaxies, int row) {
for (Integer[] galaxy: galaxies) {
if (galaxy[0] == row) {
return false;
}
}
return true;
}
private static void moveDown(ArrayList<Integer[]> galaxies, int row, int dist) {
for (Integer[] galaxy: galaxies) {
if (galaxy[0] > row) {
galaxy[0] += dist;
}
}
}
private static boolean colEmpty(ArrayList<Integer[]> galaxies, int col) {
for (Integer[] galaxy: galaxies) {
if (galaxy[1] == col) {
return false;
}
}
return true;
}
private static void moveRight(ArrayList<Integer[]> galaxies, int col, int dist) {
for (Integer[] galaxy: galaxies) {
if (galaxy[1] > col) {
galaxy[1] += dist;
}
}
}
}
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