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import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
public class day08 {
public static void main(String args[]) throws IOException {
RandomAccessFile input = new RandomAccessFile("input", "r");
System.out.println("Day 08 Part 1: " + part1(input));
input.seek(0);
System.out.println("Day 08 Part 2: " + part2(input));
input.close();
}
public static String part1(RandomAccessFile input) throws IOException {
char[] instr = input.readLine().toCharArray();
input.readLine();
Pattern nodepat = Pattern.compile("[A-Z]{3}");
HashMap<String, Node> nodes = new HashMap<>();
String line;
while ((line = input.readLine()) != null) {
Matcher mat = nodepat.matcher(line);
mat.find();
String name = mat.group();
mat.find();
String left = mat.group();
mat.find();
String right = mat.group();
Node node;
if (nodes.containsKey(name)) {
node = nodes.get(name);
} else {
node = new Node(name);
nodes.put(name, node);
}
if (nodes.containsKey(left)) {
node.left = nodes.get(left);
} else {
node.left = new Node(left);
nodes.put(left, node.left);
}
if (nodes.containsKey(right)) {
node.right = nodes.get(right);
} else {
node.right = new Node(right);
nodes.put(right, node.right);
}
}
Node at = nodes.get("AAA");
int count = 0, ip = 0;
while (!(at.name.equals("ZZZ"))) {
if (instr[ip] == 'L') {
at = at.left;
} else {
at = at.right;
}
count += 1;
ip += 1;
ip %= instr.length;
}
return Integer.toString(count);
}
public static String part2(RandomAccessFile input) throws IOException {
char[] instr = input.readLine().toCharArray();
input.readLine();
Pattern nodepat = Pattern.compile("[A-Z]{3}");
HashMap<String, Node> nodes = new HashMap<>();
String line;
while ((line = input.readLine()) != null) {
Matcher mat = nodepat.matcher(line);
mat.find();
String name = mat.group();
mat.find();
String left = mat.group();
mat.find();
String right = mat.group();
Node node;
if (nodes.containsKey(name)) {
node = nodes.get(name);
} else {
node = new Node(name);
nodes.put(name, node);
}
if (nodes.containsKey(left)) {
node.left = nodes.get(left);
} else {
node.left = new Node(left);
nodes.put(left, node.left);
}
if (nodes.containsKey(right)) {
node.right = nodes.get(right);
} else {
node.right = new Node(right);
nodes.put(right, node.right);
}
}
ArrayList<Node> ats = new ArrayList<>();
for (String name: nodes.keySet()) {
if (name.charAt(2) == 'A') {
ats.add(nodes.get(name));
}
}
int count = 0, ip = 0;
boolean allatz = false;
while (!allatz) {
if (instr[ip] == 'L') {
for (int i = 0; i < ats.size(); i++) {
ats.set(i, ats.get(i).left);
}
} else {
for (int i = 0; i < ats.size(); i++) {
ats.set(i, ats.get(i).right);
}
}
count += 1;
ip += 1;
ip %= instr.length;
allatz = true;
for (Node at: ats) {
if (!(at.name.charAt(2) == 'Z')) {
allatz = false;
}
}
}
return Integer.toString(count);
}
}
class Node {
String name;
Node left, right;
public Node(String name) {
this.name = name;
this.left = null;
this.right = null;
}
public String toString() {
return this.name + " = (" + this.left.name + ", " + this.right.name + ")";
}
}
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