feat: solve day 2

Author: Flashky

src/main/java/com/adventofcode/flashk/day02/README.md

@@ -1,3 +1,3 @@
-# Day 2: 
+# Day 2: Red-Nosed Reports
 
 [https://adventofcode.com/2024/day/2](https://adventofcode.com/2024/day/2)

src/main/java/com/adventofcode/flashk/day02/RedNosedReports.java

@@ -0,0 +1,34 @@
+package com.adventofcode.flashk.day02;
+
+import java.util.List;
+
+public class RedNosedReports {
+
+    private List<Report> reports;
+
+    public RedNosedReports(List<String> inputs) {
+        reports = inputs.stream().map(Report::new).toList();
+    }
+
+    public int solveA() {
+        int result = 0;
+        for(Report report : reports) {
+            if(report.isSafe()) {
+                result++;
+            }
+        }
+
+        return result;
+    }
+
+    public int solveB() {
+        int result = 0;
+        for(Report report : reports) {
+            if(report.isSafeDampener()) {
+                result++;
+            }
+        }
+
+        return result;
+    }
+}

src/main/java/com/adventofcode/flashk/day02/Report.java

@@ -0,0 +1,96 @@
+package com.adventofcode.flashk.day02;
+
+import lombok.Getter;
+import lombok.Setter;
+import org.apache.commons.lang3.StringUtils;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.List;
+import java.util.stream.Collectors;
+
+@Getter
+@Setter
+public class Report {
+
+    private List<Integer> levels;
+
+    public Report(String input) {
+        // Warning: do not use .toList() as it would create an immutable list
+        levels = Arrays.stream(input.split(StringUtils.SPACE)).map(Integer::valueOf).collect(Collectors.toList());
+    }
+
+    public boolean isSafe() {
+        boolean expectedIncreasing = isIncreasing();
+        boolean isSafe = true;
+
+        int i = 1;
+        int lastLevel = levels.get(0);
+
+        while(isSafe && i < levels.size()) {
+            int currentLevel = levels.get(i);
+            int distance = currentLevel-lastLevel;
+
+            if(distance == 0) {
+                isSafe = false;
+            } else if(expectedIncreasing) {
+                if(distance > 3 || distance < 0) {
+                    isSafe = false;
+                }
+            } else {
+                if(distance < -3 || distance > 0) {
+                    isSafe = false;
+                }
+            }
+
+            lastLevel = currentLevel;
+            i++;
+        }
+
+        return isSafe;
+    }
+
+    public boolean isSafeDampener() {
+        if(isSafe()) {
+            return true;
+        }
+
+        List<Integer> copyLevels = new ArrayList<>(levels);
+
+        boolean isSafe = false;
+        int i = 0;
+
+        while(!isSafe && i < levels.size()) {
+
+            levels.remove(i);
+            isSafe = isSafe();
+
+            if(!isSafe()) {
+                levels = new ArrayList<>(copyLevels);
+                i++;
+            }
+        }
+
+        return isSafe;
+    }
+    /**
+     * true si creciente
+     * false si decreciente;
+     * @return
+     */
+    private boolean isIncreasing() {
+        int i = 0;
+        boolean found = false;
+        int distance = 0;
+        while(!found && i < levels.size()-1) {
+            distance = levels.get(i+1)-levels.get(i);
+            if(distance != 0) {
+                found = true;
+            }
+            i++;
+        }
+
+        return distance > 0;
+    }
+}

src/test/java/com/adventofcode/flashk/day02/Day02Test.java

@@ -19,9 +19,10 @@
 import com.adventofcode.flashk.common.test.utils.Timer;
 import com.adventofcode.flashk.common.test.utils.Input;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 @DisplayName(TestDisplayName.DAY_02)
 @TestMethodOrder(OrderAnnotation.class)
-@Disabled // TODO Remove comment when implemented
 public class Day02Test extends PuzzleTest {
 
 	private final static String INPUT_FOLDER = TestFolder.DAY_02;
@@ -43,7 +44,9 @@ public void testSolvePart1Sample() {
 
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE_SAMPLE);
-		
+
+		RedNosedReports reports = new RedNosedReports(inputs);
+		assertEquals(2,reports.solveA());
 	}
 
 	@Test
@@ -57,8 +60,11 @@ public void testSolvePart1Input() {
 
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE);
-		
+		RedNosedReports reports = new RedNosedReports(inputs);
+
+		assertEquals(257,reports.solveA());
 	}
+
 
 	@Test
 	@Order(3)
@@ -71,7 +77,9 @@ public void testSolvePart2Sample() {
 
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE_SAMPLE);
-		
+		RedNosedReports reports = new RedNosedReports(inputs);
+
+		assertEquals(4, reports.solveB());
 	}
 
 	@Test
@@ -85,6 +93,9 @@ public void testSolvePart2Input() {
 
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE);
+		RedNosedReports reports = new RedNosedReports(inputs);
+
+		assertEquals(328, reports.solveB());
 
 	}