day01 for AoC 2023 (part 1)

Took 23 minutes

Author: albertominetti

src/main/java/aminetti/adventofcode2024/day01/Day01.java

@@ -0,0 +1,52 @@
+package aminetti.adventofcode2024.day01;
+
+import com.google.common.collect.Streams;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.math.BigInteger;
+import java.sql.Array;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class Day01 {
+    private static final Logger LOGGER = LoggerFactory.getLogger(Day01.class);
+    private List<String> input;
+
+    public Day01() {
+    }
+
+    public void parseInput(List<String> input) {
+        this.input = input;
+    }
+
+    public long solvePart1() {
+        Pattern p = Pattern.compile("(\\d+)\\s+(\\d+)");
+
+        ArrayList<Integer> left = new ArrayList<>(input.size());
+        ArrayList<Integer> right = new ArrayList<>(input.size());
+
+        for (String s : input) {
+            Matcher matcher = p.matcher(s);
+            if (matcher.matches()) {
+                Integer a = Integer.valueOf(matcher.group(1));
+                Integer b = Integer.valueOf(matcher.group(2));
+                LOGGER.info("Reading: {} and {}", a ,b);
+                left.add(a);
+                right.add(b);
+            } else {
+                throw new IllegalArgumentException("Invalid input: " + s);
+            }
+        }
+
+        return Streams.zip(left.stream().sorted(), right.stream().sorted(),
+                (a, b) -> Math.abs(a-b)).reduce(0, (a, b) -> a + b);
+    }
+
+    public long solvePart2() {
+
+        return 0;
+    }
+}

src/test/java/aminetti/adventofcode2024/day01/Day01Test.java

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+package aminetti.adventofcode2024.day01;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.util.List;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.apache.commons.io.IOUtils.readLines;
+import static org.apache.commons.io.IOUtils.resourceToString;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+
+class Day01Test {
+
+    @Test
+    void actualInputPart1() throws IOException {
+        // given
+        List<String> input = readLines(resourceToString("/day01/day01_input.txt", UTF_8));
+
+        // when
+        Day01 solver = new Day01();
+        solver.parseInput(input);
+        long l = solver.solvePart1();
+
+        // then
+        assertThat(l, is(110396520L));
+    }
+
+    @Test
+    void testInputPart1() throws IOException {
+        // given
+        List<String> input = readLines(resourceToString("/day01/day01_input_test.txt", UTF_8));
+
+        // when
+        Day01 solver = new Day01();
+        solver.parseInput(input);
+        long l = solver.solvePart1();
+
+        // then
+        assertThat(l, is(11L));
+    }
+
+    @Test
+    void actualInputPart2() throws IOException {
+        // given
+        List<String> input = readLines(resourceToString("/day01/day01_input.txt", UTF_8));
+
+        // when
+        Day01 solver = new Day01();
+        solver.parseInput(input);
+        long l = solver.solvePart2();
+
+        // then
+        assertThat(l, is(11L));
+    }
+
+    @Test
+    void testInputPart2() throws IOException {
+        // given
+        List<String> input = readLines(resourceToString("/day01/day01_input_test.txt", UTF_8));
+
+        // when
+        Day01 solver = new Day01();
+        solver.parseInput(input);
+        long l = solver.solvePart2();
+
+        // then
+        assertThat(l, is(0L));
+    }
+
+
+}