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TheCKTheCK
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AOC 2025 day 2
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Lines changed: 83 additions & 15 deletions

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‎adventofcode/README.md‎

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[20242402tests]: src/test/java/org/ck/adventofcode/year2024/Day24Test.java
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[20242501tests]: src/test/java/org/ck/adventofcode/year2024/Day25Test.java
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# 2025 (2/24)
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# 2025 (4/24)
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| # | Name | Solution | Test |
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|---------:|---------------------------------------------|:------------------------------------:|:---------------------------------:|
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| 20250101 | [Day 1: Secret Entrance][20250101] | ✅[💾][20250101solution] | ✅[💾][20250101tests] |
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| 20250102 | [Day 1: Secret Entrance - Part 2][20250102] | ✅[💾][20250102solution] | ✅[💾][20250102tests] |
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| 20250201 | [Day 2: ][20250201] | [💾][20250201solution] | [💾][20250201tests] |
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| 20250202 | [Day 2: - Part 2][20250202] | [💾][20250202solution] | [💾][20250202tests] |
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| 20250201 | [Day 2: Gift Shop][20250201] | ✅[💾][20250201solution] | ✅[💾][20250201tests] |
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| 20250202 | [Day 2: Gift Shop - Part 2][20250202] | ✅[💾][20250202solution] | ✅[💾][20250202tests] |
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| 20250301 | [Day 3: ][20250301] | [💾][20250301solution] | [💾][20250301tests] |
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| 20250302 | [Day 3: - Part 2][20250302] | [💾][20250302solution] | [💾][20250302tests] |
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| 20250401 | [Day 4: ][20250401] | [💾][20250401solution] | [💾][20250401tests] |

‎adventofcode/src/main/java/org/ck/adventofcode/year2025/Day02.java‎

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package org.ck.adventofcode.year2025;
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import java.util.HashSet;
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import java.util.Scanner;
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import java.util.Set;
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import java.util.function.ToIntFunction;
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import java.util.regex.Matcher;
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import java.util.regex.Pattern;
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import org.ck.adventofcode.util.AOCSolution;
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import org.ck.codechallengelib.annotation.Solution;
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@Solution(
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id = 20250201,
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name = "Day 2: ",
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name = "Day 2: Gift Shop",
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url = "https://adventofcode.com/2025/day/2",
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category = "2025",
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solved = false)
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category = "2025")
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@Solution(
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id = 20250202,
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name = "Day 2: - Part 2",
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name = "Day 2: Gift Shop - Part 2",
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url = "https://adventofcode.com/2025/day/2#part2",
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category = "2025",
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solved = false)
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category = "2025")
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public class Day02 extends AOCSolution {
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static final Pattern rangePattern = Pattern.compile("(?<start>\\d+)-(?<end>\\d+)");
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@Override
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protected void runPartOne(final Scanner in) {
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run(in);
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run(in, _ -> 2);
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}
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@Override
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protected void runPartTwo(final Scanner in) {
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run(in);
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run(in, startLength -> startLength);
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}
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private void run(final Scanner in) {
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// not yet implemented
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private void run(final Scanner in, final ToIntFunction<Integer> getMaxRepetitions) {
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final String[] ranges = in.nextLine().split(",");
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final Set<Long> invalidIds = new HashSet<>();
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for (final String range : ranges) {
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final Matcher matcher = rangePattern.matcher(range);
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if (matcher.find()) {
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final String startString = matcher.group("start");
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final String endString = matcher.group("end");
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final long end = Long.parseLong(endString);
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for (int repetitions = 2;
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repetitions <= getMaxRepetitions.applyAsInt(endString.length());
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++repetitions) {
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invalidIds.addAll(generateInvalidIds(repetitions, startString, end));
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}
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}
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}
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print(invalidIds.stream().mapToLong(Long::longValue).sum());
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}
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private static Set<Long> generateInvalidIds(
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final int repetitions, final String startString, final long end) {
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final long start = Long.parseLong(startString);
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final int startLength = startString.length();
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final int halfLength = startLength / repetitions;
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final long startHalf =
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halfLength > 0 ? Long.parseLong(startString.substring(0, halfLength)) : 1;
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final Set<Long> invalidIds = new HashSet<>();
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for (long numberHalf = startHalf; ; ++numberHalf) {
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final long number = getInvalidId(numberHalf, repetitions);
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if (number > end) {
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break;
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}
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if (number >= start) {
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invalidIds.add(number);
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}
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}
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return invalidIds;
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}
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private static long getInvalidId(final long numberHalf, final int repetitions) {
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final int currentLength = (int) Math.log10(numberHalf) + 1;
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final long shiftAmount = (long) Math.pow(10, currentLength);
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long number = numberHalf;
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for (int i = 1; i < repetitions; ++i) {
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number *= shiftAmount;
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number += numberHalf;
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}
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return number;
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}
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}

‎adventofcode/src/test/java/org/ck/adventofcode/year2025/Day02Test.java‎

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package org.ck.adventofcode.year2025;
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import org.ck.adventofcode.util.BaseAOCTest;
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import org.junit.jupiter.api.Disabled;
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import org.junit.jupiter.params.ParameterizedTest;
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import org.junit.jupiter.params.provider.ValueSource;
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@Disabled
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class Day02Test extends BaseAOCTest {
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@ParameterizedTest
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@ValueSource(strings = {"01a"})

‎adventofcode/src/test/resources/org/ck/adventofcode/year2025/day02/01.result.txt‎

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9188031749

‎adventofcode/src/test/resources/org/ck/adventofcode/year2025/day02/01.txt‎

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7CFSkaJB5BuU4L0UpjPkcQ==@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

‎adventofcode/src/test/resources/org/ck/adventofcode/year2025/day02/01a.result.txt‎

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1227775554

‎adventofcode/src/test/resources/org/ck/adventofcode/year2025/day02/01a.txt‎

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11-22,95-115,998-1012,1188511880-1188511890,222220-222224,1698522-1698528,446443-446449,38593856-38593862,565653-565659,824824821-824824827,2121212118-2121212124

‎adventofcode/src/test/resources/org/ck/adventofcode/year2025/day02/02.result.txt‎

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11323661261

‎adventofcode/src/test/resources/org/ck/adventofcode/year2025/day02/02.txt‎

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7CFSkaJB5BuU4L0UpjPkcQ==@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

‎adventofcode/src/test/resources/org/ck/adventofcode/year2025/day02/02a.result.txt‎

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4174379265

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