feat: solve day 1

Author: Flashky

src/main/java/com/adventofcode/flashk/day01/HistorianHysteria.java

@@ -0,0 +1,62 @@
+package com.adventofcode.flashk.day01;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class HistorianHysteria {
+
+    private List<Long> left = new ArrayList<>();
+    private List<Long> right = new ArrayList<>();
+
+    public HistorianHysteria(List<String> input) {
+        for(String line : input) {
+            String[] split = line.split("   ");
+            left.add(Long.valueOf(split[0]));
+            right.add(Long.valueOf(split[1]));
+        }
+    }
+
+    public Long solveA() {
+        List<Long> leftSorted = left.stream().sorted().toList();
+        List<Long> rightSorted = right.stream().sorted().toList();
+
+        Long result = 0L;
+
+        for(int i  = 0; i < leftSorted.size(); i++) {
+            result += Math.abs(leftSorted.get(i)-rightSorted.get(i));
+        }
+
+        return result;
+    }
+
+    public Long solveB() {
+
+        Long result = 0L;
+        Map<Long,Long> numberOccurrences = new HashMap<>();
+
+        for(Long number : left) {
+            Long occurrences = 0L;
+            if(numberOccurrences.containsKey(number)) {
+                occurrences = numberOccurrences.get(number);
+                result += number * numberOccurrences.get(number);
+            } else {
+
+                for(Long numberRight : right) {
+                    if(number.equals(numberRight)) {
+                        occurrences++;
+                    }
+                }
+
+                numberOccurrences.put(number, occurrences);
+            }
+            result += number * occurrences;
+
+        }
+
+        return result;
+    }
+
+
+}

src/test/java/com/adventofcode/flashk/day01/Day01Test.java

@@ -19,6 +19,8 @@
 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_01)
 @TestMethodOrder(OrderAnnotation.class)
 public class Day01Test extends PuzzleTest {
@@ -42,7 +44,10 @@ public void testSolvePart1Sample() {
 
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE_SAMPLE);
-		
+
+		HistorianHysteria historianHysteria = new HistorianHysteria(inputs);
+
+		assertEquals(11, historianHysteria.solveA());
 	}
 
 	@Test
@@ -56,7 +61,10 @@ public void testSolvePart1Input() {
 
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE);
-		
+		HistorianHysteria historianHysteria = new HistorianHysteria(inputs);
+
+		assertEquals(3574690, historianHysteria.solveA());
+
 	}
 
 	@Test
@@ -70,7 +78,10 @@ public void testSolvePart2Sample() {
 
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE_SAMPLE);
-		
+
+		HistorianHysteria historianHysteria = new HistorianHysteria(inputs);
+
+		assertEquals(31, historianHysteria.solveB());
 	}
 
 	@Test
@@ -84,6 +95,10 @@ public void testSolvePart2Input() {
 
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE);
+
+		HistorianHysteria historianHysteria = new HistorianHysteria(inputs);
+
+		assertEquals(22565391, historianHysteria.solveB());
 
 	}