Добрался до пятого дня AoC. Вообще, по ощущениям, сами алгоритмы пока становятся проще от задачи к задаче. А вот пред-обработка исходных данных начинает требовать времени.
Начальное состояние склада просто захардкодил, слегка покрутив в Calc (для бо́льшего удобства копипаста). В конце заметки приведу некоторые подробности.
Поскольку мутируются стеки ящиков “на месте” – для корректного решения второй части приходится использовать копию начального состояния склада.
static void day5(String puzzleInputUri) throws IOException, InterruptedException {
/*
[V] [C] [M]
[V] [J] [N] [H] [V]
[R] [F] [N] [W] [Z] [N]
[H] [R] [D] [Q] [M] [L] [B]
[B] [C] [H] [V] [R] [C] [G] [R]
[G] [G] [F] [S] [D] [H] [B] [R] [S]
[D] [N] [S] [D] [H] [G] [J] [J] [G]
[W] [J] [L] [J] [S] [P] [F] [S] [L]
1 2 3 4 5 6 7 8 9
*/
Stack<String> stack1 = new Stack<>();
stack1.addAll(List.of("W","D","G","B","H","R","V"));
Stack<String> stack2 = new Stack<>();
stack2.addAll(List.of("J","N","G","C","R","F"));
Stack<String> stack3 = new Stack<>();
stack3.addAll(List.of("L","S","F","H","D","N","J"));
Stack<String> stack4 = new Stack<>();
stack4.addAll(List.of("J","D","S","V"));
Stack<String> stack5 = new Stack<>();
stack5.addAll(List.of("V","S","H","D","R","Q","W","N","V"));
Stack<String> stack6 = new Stack<>();
stack6.addAll(List.of("P","G","H","C","M"));
Stack<String> stack7 = new Stack<>();
stack7.addAll(List.of("C","F","J","B","G","L","Z","H","C"));
Stack<String> stack8 = new Stack<>();
stack8.addAll(List.of("S","J","R"));
Stack<String> stack9 = new Stack<>();
stack9.addAll(List.of("M","L","G","S","R","B","N","V","M"));
Map<Integer, Stack<String>> wareHousePartOne = new TreeMap<>(Map.of(
1, stack1, 2, stack2, 3, stack3, 4, stack4,
5, stack5, 6, stack6, 7, stack7, 8, stack8,
9, stack9
));
Map<Integer, Stack<String>> wareHousePartTwo = new TreeMap<>();
wareHousePartOne.forEach((stackN, stack) -> {
var wh2Stack = new Stack<String>();
wh2Stack.addAll(stack);
wareHousePartTwo.put(stackN, wh2Stack);
});
client.send(request.uri((URI.create(puzzleInputUri))).build(), HttpResponse.BodyHandlers.ofLines()).body()
.dropWhile(s -> !s.contains("move"))
.map(s -> s.split(" "))
.forEach(action -> {
int count = Integer.parseInt(action[1]);
int fromStack = Integer.parseInt(action[3]);
int toStack = Integer.parseInt(action[5]);
for (int i = 0; i < count; i++) {
String crate = wareHousePartOne.get(fromStack).pop();
wareHousePartOne.get(toStack).push(crate);
}
});
StringBuilder upperCrates = new StringBuilder();
wareHousePartOne.values().forEach(stack -> upperCrates.append(stack.pop()));
System.out.println(upperCrates);
client.send(request.uri((URI.create(puzzleInputUri))).build(), HttpResponse.BodyHandlers.ofLines()).body()
.dropWhile(s -> !s.contains("move"))
.map(s -> s.split(" "))
.forEach(action -> {
int count = Integer.parseInt(action[1]);
int fromStack = Integer.parseInt(action[3]);
int toStack = Integer.parseInt(action[5]);
List<String> cratesBuffer = new ArrayList<>();
for (int i = 0; i < count; i++) {
cratesBuffer.add(wareHousePartTwo.get(fromStack).pop());
}
Collections.reverse(cratesBuffer);
cratesBuffer.forEach(crate -> wareHousePartTwo.get(toStack).push(crate));
});
StringBuilder upperCratesPartTwo = new StringBuilder();
wareHousePartTwo.values().forEach(stack -> upperCratesPartTwo.append(stack.pop()));
System.out.println(upperCratesPartTwo);
}
Либо – просто между вызовами для решения разных частей – поменять внутрянку перестановки ящиков:
List<String> cratesBuffer = new ArrayList<>();
for (int i = 0; i < count; i++) {
cratesBuffer.add(wareHouse.get(fromStack).pop());
}
Collections.reverse(cratesBuffer);
cratesBuffer.forEach(crate -> wareHouse.get(toStack).push(crate));
Исходные данные: https://adventofcode.com/2022/day/5/input
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