AoC 2023 Day 2 - java

README.md

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 | ---| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
 | python3 | [✓](src/main/python/AoC2023_01.py) | [✓](src/main/python/AoC2023_02.py) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
-| java | [✓](src/main/java/AoC2023_01.java) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
+| java | [✓](src/main/java/AoC2023_01.java) | [✓](src/main/java/AoC2023_02.java) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
 | bash |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
 | c++ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
 | julia |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

src/main/java/AoC2023_02.java

@@ -0,0 +1,94 @@
+import static com.github.pareronia.aoc.Utils.enumerate;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.Function;
+import java.util.function.Predicate;
+
+import com.github.pareronia.aoc.solution.Sample;
+import com.github.pareronia.aoc.solution.Samples;
+import com.github.pareronia.aoc.solution.SolutionBase;
+
+public final class AoC2023_02
+        extends SolutionBase<List<AoC2023_02.Game>, Integer, Integer> {
+
+    private AoC2023_02(final boolean debug) {
+        super(debug);
+    }
+
+    public static AoC2023_02 create() {
+        return new AoC2023_02(false);
+    }
+
+    public static AoC2023_02 createDebug() {
+        return new AoC2023_02(true);
+    }
+
+    @Override
+    protected List<Game> parseInput(final List<String> inputs) {
+        final Function<String, Draw> parseDraw = s -> {
+            int red = 0, green = 0, blue = 0;
+            for (final String cc : s.split(",")) {
+                final String[] splits = cc.strip().split(" ");
+                final String color = splits[1];
+                if ("red".equals(color)) {
+                    red = Integer.parseInt(splits[0]);
+                } else if ("green".equals(color)) {
+                    green = Integer.parseInt(splits[0]);
+                } else {
+                    blue = Integer.parseInt(splits[0]);
+                }
+            }
+            return new Draw(red, green, blue);
+        };
+        return enumerate(inputs.stream())
+            .map(e -> new Game(
+                e.getIndex() + 1,
+                Arrays.stream(e.getValue().split(":")[1].split(";"))
+                    .map(parseDraw).toList()))
+            .toList();
+    }
+
+    @Override
+    public Integer solvePart1(final List<Game> games) {
+        final Predicate<Draw> possible = draw ->
+            draw.red <= 12 && draw.green <= 13 && draw.blue <= 14;
+        return games.stream()
+            .filter(game -> game.draws.stream().allMatch(possible))
+            .mapToInt(Game::id)
+            .sum();
+    }
+
+    @Override
+    public Integer solvePart2(final List<Game> games) {
+        final Function<Game, Integer> power = game ->
+                game.draws.stream().mapToInt(Draw::red).max().getAsInt()
+              * game.draws.stream().mapToInt(Draw::green).max().getAsInt()
+              * game.draws.stream().mapToInt(Draw::blue).max().getAsInt();
+        return games.stream().mapToInt(power::apply).sum();
+    }
+
+    @Override
+    @Samples({
+        @Sample(method = "part1", input = TEST, expected = "8"),
+        @Sample(method = "part2", input = TEST, expected = "2286"),
+    })
+    public void samples() {
+    }
+
+    public static void main(final String[] args) throws Exception {
+        AoC2023_02.create().run();
+    }
+
+    private record Draw(int red, int green, int blue) { }
+
+    record Game(int id, List<Draw> draws) { }
+
+    private static final String TEST = """
+        Game 1: 3 blue, 4 red; 1 red, 2 green, 6 blue; 2 green
+        Game 2: 1 blue, 2 green; 3 green, 4 blue, 1 red; 1 green, 1 blue
+        Game 3: 8 green, 6 blue, 20 red; 5 blue, 4 red, 13 green; 5 green, 1 red
+        Game 4: 1 green, 3 red, 6 blue; 3 green, 6 red; 3 green, 15 blue, 14 red
+        Game 5: 6 red, 1 blue, 3 green; 2 blue, 1 red, 2 green
+        """;
+}