Advent of Code 2017 - Day 13

Day13.java

package Advent2017;

import util.FileIO;
import util.Timer;

import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

public class Day13 {

    public static void main(String[] args) {

        Map<Integer, Integer> map;
        List<int[]> input = FileIO.getFileLinesSplitAsInt("advent2017_day13.txt", ": ");

        Timer.startTimer();
        map = input.stream()
                .collect(Collectors.toMap(x -> x[0], x -> x[1]));


        int severity = map.entrySet().stream()
                .filter(x -> x.getKey() % ((x.getValue() - 1) * 2) == 0)
                .mapToInt(x -> x.getKey() * x.getValue())
                .sum();

        System.out.println("Part 1:" + severity);

        int delay = 2;

        while (true) {
            boolean caught = false;

            for (Map.Entry<Integer, Integer> layer : map.entrySet()) {
                if ((layer.getKey() + delay) % ((layer.getValue() - 1) * 2) == 0) {
                    caught = true;
                    break;
                }
            }
            if (!caught) break;
            delay+= 2;

        }
        System.out.println("Part 2: " + delay);
        System.out.println(Timer.endTimer());
    }
}