aoc 2024 day 2

adventofcode/README.md

@@ -1422,14 +1422,14 @@
 [20232402tests]: src/test/java/org/ck/adventofcode/year2023/Day24Test.java
 [20232501tests]: src/test/java/org/ck/adventofcode/year2023/Day25Test.java
 
-# 2024 (2/49)
+# 2024 (4/49)
 
 |        # | Name                                           | Solution                             | Test                              |
 |---------:|------------------------------------------------|:------------------------------------:|:---------------------------------:|
 | 20240101 | [Day 1: Historian Hysteria][20240101]          | ✅[💾][20240101solution] | ✅[💾][20240101tests] |
 | 20240102 | [Day 1: Historian Hysteria - Part 2][20240102] | ✅[💾][20240102solution] | ✅[💾][20240102tests] |
-| 20240201 | [Day 2: ?][20240201]                           | [💾][20240201solution]        | [💾][20240201tests]        |
-| 20240202 | [Day 2: ? - Part 2][20240202]                  | [💾][20240202solution]        | [💾][20240202tests]        |
+| 20240201 | [Day 2: Red-Nosed Reports][20240201]           | ✅[💾][20240201solution] | ✅[💾][20240201tests] |
+| 20240202 | [Day 2: Red-Nosed Reports - Part 2][20240202]  | ✅[💾][20240202solution] | ✅[💾][20240202tests] |
 | 20240301 | [Day 3: ?][20240301]                           | [💾][20240301solution]        | [💾][20240301tests]        |
 | 20240302 | [Day 3: ? - Part 2][20240302]                  | [💾][20240302solution]        | [💾][20240302tests]        |
 | 20240401 | [Day 4: ?][20240401]                           | [💾][20240401solution]        | [💾][20240401tests]        |

adventofcode/src/main/java/org/ck/adventofcode/year2024/Day02.java

@@ -1,34 +1,92 @@
 package org.ck.adventofcode.year2024;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Scanner;
+import java.util.function.Function;
 import org.ck.adventofcode.util.AOCSolution;
 import org.ck.codechallengelib.annotation.Solution;
 
 @Solution(
     id = 20240201,
-    name = "Day 2: ?",
+    name = "Day 2: Red-Nosed Reports",
     url = "https://adventofcode.com/2024/day/2",
-    category = "2024",
-    solved = false)
+    category = "2024")
 @Solution(
     id = 20240202,
-    name = "Day 2: ? - Part 2",
+    name = "Day 2: Red-Nosed Reports - Part 2",
     url = "https://adventofcode.com/2024/day/2#part2",
-    category = "2024",
-    solved = false)
+    category = "2024")
 public class Day02 extends AOCSolution {
 
   @Override
   protected void runPartOne(final Scanner in) {
-    run(in);
+    run(in, List::of);
   }
 
   @Override
   protected void runPartTwo(final Scanner in) {
-    run(in);
+    run(
+        in,
+        list -> {
+          final List<List<Integer>> all = new ArrayList<>();
+          all.add(list);
+
+          for (int i = 0; i < list.size(); ++i) {
+            final List<Integer> tmp = new ArrayList<>(list);
+            tmp.remove(i);
+
+            all.add(tmp);
+          }
+
+          return all;
+        });
+  }
+
+  private void run(final Scanner in, Function<List<Integer>, List<List<Integer>>> foo) {
+    long safeCount = 0;
+
+    while (in.hasNextLine()) {
+      final List<Integer> line = readInput(in);
+
+      final List<List<Integer>> all = foo.apply(line);
+
+      for (List<Integer> t : all) {
+        final boolean ascending = t.get(0) - t.get(1) < 0;
+        boolean isSafe = true;
+
+        for (int i = 0; i < t.size() - 1; ++i) {
+          final int difference = t.get(i) - t.get(i + 1);
+
+          if (levelsAreValid(ascending, difference)) {
+            isSafe = false;
+            break;
+          }
+        }
+
+        if (isSafe) {
+          ++safeCount;
+          break;
+        }
+      }
+    }
+
+    print(safeCount);
   }
 
-  private void run(final Scanner in) {
-    print("Whoopsie");
+  private static boolean levelsAreValid(final boolean ascending, final int difference) {
+    return (ascending && difference > 0)
+        || (!ascending && difference < 0)
+        || !(Math.abs(difference) >= 1 && Math.abs(difference) <= 3);
+  }
+
+  private static List<Integer> readInput(final Scanner in) {
+    final List<Integer> line = new ArrayList<>();
+
+    for (String part : in.nextLine().split(" ")) {
+      line.add(Integer.parseInt(part));
+    }
+
+    return line;
   }
 }

adventofcode/src/test/java/org/ck/adventofcode/year2024/Day02Test.java

@@ -1,11 +1,9 @@
 package org.ck.adventofcode.year2024;
 
 import org.ck.adventofcode.util.BaseAOCTest;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 
-@Disabled
 class Day02Test extends BaseAOCTest {
   @ParameterizedTest
   @ValueSource(strings = {"01", "01a"})

adventofcode/src/test/resources/org/ck/adventofcode/year2024/day02/01.result.txt

@@ -0,0 +1 @@
+213