aoc 2017 day 12

adventofcode/README.md

@@ -406,7 +406,7 @@
 [20162402tests]: src/test/java/org/ck/adventofcode/year2016/Day24Test.java
 [20162501tests]: src/test/java/org/ck/adventofcode/year2016/Day25Test.java
 
-# 2017 (22/22)
+# 2017 (24/24)
 
 |        # | Name                                                                | Solution                             | Test                              |
 |---------:|---------------------------------------------------------------------|:------------------------------------:|:---------------------------------:|
@@ -432,6 +432,8 @@
 | 20171002 | [Day 10: Knot Hash - Part 2][20171002]                              | ✅[💾][20171002solution] | ✅[💾][20171002tests] |
 | 20171101 | [Day 11: Hex Ed][20171101]                                          | ✅[💾][20171101solution] | ✅[💾][20171101tests] |
 | 20171102 | [Day 11: Hex Ed - Part 2][20171102]                                 | ✅[💾][20171102solution] | ✅[💾][20171102tests] |
+| 20171201 | [Day 12: Digital Plumber][20171201]                                 | ✅[💾][20171201solution] | ✅[💾][20171201tests] |
+| 20171202 | [Day 12: Digital Plumber - Part 2][20171202]                        | ✅[💾][20171202solution] | ✅[💾][20171202tests] |
 
 [20170101]: https://adventofcode.com/2017/day/1
 [20170102]: https://adventofcode.com/2017/day/1#part2
@@ -455,6 +457,8 @@
 [20171002]: https://adventofcode.com/2017/day/10#part2
 [20171101]: https://adventofcode.com/2017/day/11
 [20171102]: https://adventofcode.com/2017/day/11#part2
+[20171201]: https://adventofcode.com/2017/day/12
+[20171202]: https://adventofcode.com/2017/day/12#part2
 
 [20170101solution]: src/main/java/org/ck/adventofcode/year2017/Day01.java
 [20170102solution]: src/main/java/org/ck/adventofcode/year2017/Day01.java
@@ -478,6 +482,8 @@
 [20171002solution]: src/main/java/org/ck/adventofcode/year2017/Day10.java
 [20171101solution]: src/main/java/org/ck/adventofcode/year2017/Day11.java
 [20171102solution]: src/main/java/org/ck/adventofcode/year2017/Day11.java
+[20171201solution]: src/main/java/org/ck/adventofcode/year2017/Day12.java
+[20171202solution]: src/main/java/org/ck/adventofcode/year2017/Day12.java
 
 [20170101tests]: src/test/java/org/ck/adventofcode/year2017/Day01Test.java
 [20170102tests]: src/test/java/org/ck/adventofcode/year2017/Day01Test.java
@@ -501,6 +507,8 @@
 [20171002tests]: src/test/java/org/ck/adventofcode/year2017/Day10Test.java
 [20171101tests]: src/test/java/org/ck/adventofcode/year2017/Day11Test.java
 [20171102tests]: src/test/java/org/ck/adventofcode/year2017/Day11Test.java
+[20171201tests]: src/test/java/org/ck/adventofcode/year2017/Day12Test.java
+[20171202tests]: src/test/java/org/ck/adventofcode/year2017/Day12Test.java
 
 # 2019 (29/30)
 

adventofcode/src/main/java/org/ck/adventofcode/year2017/Day12.java

@@ -0,0 +1,87 @@
+package org.ck.adventofcode.year2017;
+
+import java.util.*;
+import java.util.function.ToIntFunction;
+import java.util.stream.Collectors;
+import org.ck.adventofcode.util.AOCSolution;
+import org.ck.codechallengelib.annotation.Solution;
+
+@Solution(
+    id = 20171201,
+    name = "Day 12: Digital Plumber",
+    url = "https://adventofcode.com/2017/day/12",
+    category = "2017")
+@Solution(
+    id = 20171202,
+    name = "Day 12: Digital Plumber - Part 2",
+    url = "https://adventofcode.com/2017/day/12#part2",
+    category = "2017")
+public class Day12 extends AOCSolution {
+  @Override
+  protected void runPartOne(final Scanner in) {
+    run(in, Day12::getReachableFromZero);
+  }
+
+  @Override
+  protected void runPartTwo(final Scanner in) {
+    run(in, Day12::getGroupCount);
+  }
+
+  private void run(final Scanner in, final ToIntFunction<Map<Integer, Set<Integer>>> getResult) {
+    final Map<Integer, Set<Integer>> programs = new HashMap<>();
+
+    while (in.hasNextLine()) {
+      final String[] parts = in.nextLine().split(" <-> ");
+
+      programs.put(
+          Integer.parseInt(parts[0]),
+          Arrays.stream(parts[1].split(", ")).map(Integer::parseInt).collect(Collectors.toSet()));
+    }
+
+    print(getResult.applyAsInt(programs));
+  }
+
+  private static int getReachableFromZero(final Map<Integer, Set<Integer>> programs) {
+    final Set<Integer> reachable = new HashSet<>();
+    final Queue<Integer> queue = new LinkedList<>();
+    queue.add(0);
+
+    while (!queue.isEmpty()) {
+      final int current = queue.poll();
+      if (reachable.contains(current)) {
+        continue;
+      }
+
+      reachable.add(current);
+      queue.addAll(programs.get(current));
+    }
+
+    return reachable.size();
+  }
+
+  private static int getGroupCount(Map<Integer, Set<Integer>> programs) {
+    final Set<Integer> reached = new HashSet<>();
+
+    int groups = 0;
+    for (final int program : programs.keySet()) {
+      if (!reached.contains(program)) {
+        ++groups;
+
+        final Queue<Integer> queue = new LinkedList<>();
+        queue.add(program);
+
+        while (!queue.isEmpty()) {
+          final int current = queue.poll();
+          if (reached.contains(current)) {
+            continue;
+          }
+
+          reached.add(current);
+          queue.addAll(programs.get(current));
+        }
+      }
+    }
+
+    return groups;
+  }
+}

adventofcode/src/test/java/org/ck/adventofcode/year2017/Day12Test.java

@@ -0,0 +1,19 @@
+package org.ck.adventofcode.year2017;
+
+import org.ck.adventofcode.util.BaseAOCTest;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+class Day12Test extends BaseAOCTest {
+  @ParameterizedTest
+  @ValueSource(strings = {"01a"})
+  void testPartOneExamples(final String name) throws Exception {
+    runTest(new Day12()::partOne, "day12/%s".formatted(name));
+  }
+
+  @ParameterizedTest
+  @ValueSource(strings = {"02a"})
+  void testPartTwoExamples(final String name) throws Exception {
+    runTest(new Day12()::partTwo, "day12/%s".formatted(name));
+  }
+}

adventofcode/src/test/resources/org/ck/adventofcode/year2017/day12/01.result.txt

@@ -0,0 +1 @@
+130

adventofcode/src/test/resources/org/ck/adventofcode/year2017/day12/01a.result.txt

@@ -0,0 +1 @@
+6

adventofcode/src/test/resources/org/ck/adventofcode/year2017/day12/01a.txt

@@ -0,0 +1,7 @@
+0 <-> 2
+1 <-> 1
+2 <-> 0, 3, 4
+3 <-> 2, 4
+4 <-> 2, 3, 6
+5 <-> 6
+6 <-> 4, 5

adventofcode/src/test/resources/org/ck/adventofcode/year2017/day12/02.result.txt

@@ -0,0 +1 @@
+189

adventofcode/src/test/resources/org/ck/adventofcode/year2017/day12/02a.result.txt

@@ -0,0 +1 @@
+2

adventofcode/src/test/resources/org/ck/adventofcode/year2017/day12/02a.txt

@@ -0,0 +1,7 @@
+0 <-> 2
+1 <-> 1
+2 <-> 0, 3, 4
+3 <-> 2, 4
+4 <-> 2, 3, 6
+5 <-> 6
+6 <-> 4, 5