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import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.ArrayList;
import java.util.AbstractMap.SimpleEntry;
public class day15 {
public static void main(String args[]) throws IOException {
RandomAccessFile input = new RandomAccessFile("input", "r");
System.out.println("Day 15 Part 1: " + part1(input));
input.seek(0);
System.out.println("Day 15 Part 2: " + part2(input));
input.close();
}
public static String part1(RandomAccessFile input) throws IOException {
String[] init = input.readLine().split(",");
int sum = 0;
for(String s: init) {
sum += hash(s);
}
return Integer.toString(sum);
}
public static String part2(RandomAccessFile input) throws IOException {
String[] init = input.readLine().split(",");
PairList[] boxes = new PairList[256];
for (int i = 0; i < 256; i++) {
boxes[i] = new PairList();
}
for (String cmd: init) {
if (cmd.endsWith("-")) {
String[] cmda = cmd.split("-");
int box = hash(cmda[0]);
boxes[box].remove(cmda[0]);
} else {
String[] cmda = cmd.split("=");
int box = hash(cmda[0]);
boxes[box].put(cmda[0], Integer.parseInt(cmda[1]));
}
}
int sum = 0;
for (int i = 0; i < 256; i++) {
sum += ((i + 1) * boxes[i].power());
}
return Integer.toString(sum);
}
private static int hash(String s) {
int cur = 0;
for (int a: s.toCharArray()) {
cur += a;
cur *= 17;
cur %= 256;
}
return cur;
}
static class PairList {
ArrayList<SimpleEntry<String, Integer>> pairlist;
public PairList() {
pairlist = new ArrayList<>();
}
public void remove(String key) {
for (int i = 0; i < pairlist.size(); i++) {
if (pairlist.get(i).getKey().equals(key)) {
pairlist.remove(i);
return;
}
}
}
public void put(String key, Integer value) {
for (int i = 0; i < pairlist.size(); i++) {
if (pairlist.get(i).getKey().equals(key)) {
pairlist.get(i).setValue(value);
return;
}
}
pairlist.add(new SimpleEntry(key, value));
}
public int power() {
int sum = 0;
for (int i = 0; i < pairlist.size(); i++) {
sum += ((i + 1) * pairlist.get(i).getValue());
}
return sum;
}
}
}
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