1 files changed, 158 insertions, 0 deletions
diff --git a/day05/day05.java b/day05/day05.java
new file mode 100644
index 0000000..d7d7992
--- /dev/null
+++ b/day05/day05.java
@@ -0,0 +1,158 @@
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.regex.Pattern;
+
+public class day05 {
+  public static void main(String args[]) throws IOException {
+    RandomAccessFile input = new RandomAccessFile("input", "r");
+    System.out.println("Day 05 Part 1: " + part1(input));
+    input.seek(0);
+    System.out.println("Day 05 Part 2: " + part2(input));
+    input.close();
+  }
+
+  public static String part1(RandomAccessFile input) throws IOException {
+    Garden garden = parseGarden(input);
+    
+    long min_loc = Long.MAX_VALUE;
+    for (long seed: garden.seeds) {
+      long loc = garden.location(seed);
+      if (loc < min_loc) {
+        min_loc = loc;
+      }
+    }
+
+    return Long.toString(min_loc);
+  }
+
+  public static String part2(RandomAccessFile input) throws IOException {
+    return "WIP";
+  }
+
+  private static Garden parseGarden(RandomAccessFile input) throws IOException {
+    Garden garden = new Garden();
+
+    String line;
+    int state = -1;
+    while ((line = input.readLine()) != null) {
+      if (Pattern.matches("\\Aseeds:.*", line)) {
+        String[] seeds = line.split(": ")[1].split(" ");
+        for (String seed: seeds) {
+          garden.seeds.add(Long.parseLong(seed));
+        }
+      } else if (Pattern.matches(".* map:\\z", line)) {
+        state += 1;
+      } else if (Pattern.matches("\\d+ \\d+ \\d+", line)) {
+        String[] linea = line.split(" ");
+        long dst = Long.parseLong(linea[0]);
+        long src = Long.parseLong(linea[1]);
+        long len = Long.parseLong(linea[2]);
+        switch (state) {
+          case 0:
+            garden.almanac.s2s.add(dst, src, len);
+            break;
+          case 1:
+            garden.almanac.s2f.add(dst, src, len);
+            break;
+          case 2:
+            garden.almanac.f2w.add(dst, src, len);
+            break;
+          case 3:
+            garden.almanac.w2l.add(dst, src, len);
+            break;
+          case 4:
+            garden.almanac.l2t.add(dst, src, len);
+            break;
+          case 5:
+            garden.almanac.t2h.add(dst, src, len);
+            break;
+          case 6:
+            garden.almanac.h2l.add(dst, src, len);
+            break;
+        }
+      }
+    }
+
+    return garden;
+  }
+}
+
+class Garden {
+  ArrayList<Long> seeds;
+  Almanac almanac;
+
+  public Garden() {
+    this.seeds = new ArrayList<>();
+    this.almanac = new Almanac();
+  }
+
+  public long location(long seed) {
+    long at = seed;
+    for (Map map: this.almanac.maps) {
+      for (MapEntry ent: map.mapEntries) {
+        if (ent.contains(at)) {
+          at = ent.map(at);
+          break;
+        }
+      }
+    }
+    return at;
+  }
+}
+
+class Almanac {
+  Map s2s, s2f, f2w, w2l, l2t, t2h, h2l;
+  ArrayList<Map> maps;
+
+  public Almanac() {
+    this.s2s = new Map();
+    this.s2f = new Map();
+    this.f2w = new Map();
+    this.w2l = new Map();
+    this.l2t = new Map();
+    this.t2h = new Map();
+    this.h2l = new Map();
+
+    ArrayList<Map> maps = new ArrayList<>();
+    maps.add(this.s2s);
+    maps.add(this.s2f);
+    maps.add(this.f2w);
+    maps.add(this.w2l);
+    maps.add(this.l2t);
+    maps.add(this.t2h);
+    maps.add(this.h2l);
+    this.maps = maps;
+  }
+}
+
+class Map {
+  ArrayList<MapEntry> mapEntries;
+
+  public Map() {
+    mapEntries = new ArrayList<>();
+  }
+
+  public void add(long dst, long src, long len) {
+    mapEntries.add(new MapEntry(dst, src, len));
+  }
+}
+
+class MapEntry {
+  long dst, src, len;
+
+  public MapEntry(long dst, long src, long len) {
+    this.dst = dst;
+    this.src = src;
+    this.len = len;
+  }
+
+  public boolean contains(long src) {
+    return src >= this.src && src < (this.src + this.len);
+  }
+
+  public long map(long src) {
+    return this.dst + (src - this.src);
+  }
+}