Leaderboard, formatting

3 files changed, 223 insertions, 221 deletions

diff --git a/README.md b/README.md
index a2276f6..489f305 100644
--- a/README.md
+++ b/README.md
@@ -42,8 +42,8 @@ These are the results from running all entries into the challenge on eight cores
 | # | Result (m:s.ms) | Implementation     | JDK | Submitter     | Notes     |
 |---|-----------------|--------------------|-----|---------------|-----------|
 | 1 | 00:02.575 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_merykittyunsafe.java)| 21.0.1-open | [Quan Anh Mai](https://github.com/merykitty) | Quan Anh Mai's implementation, using `Unsafe` |
-| 2 | 00:02.904 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_royvanrijn.java)| 21.0.1-graal | [Roy van Rijn](https://github.com/royvanrijn) | GraalVM native binary |
-| 3 | 00:03.044 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_thomaswue.java)| 21.0.1-graal | [Thomas Wuerthinger](https://github.com/thomaswue), [Quan Anh Mai](https://github.com/merykitty), [Alfonso² Peterssen](https://github.com/mukel) | GraalVM native binary |
+| 2 | 00:02.708 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_thomaswue.java)| 21.0.1-graal | [Thomas Wuerthinger](https://github.com/thomaswue), [Quan Anh Mai](https://github.com/merykitty), [Alfonso² Peterssen](https://github.com/mukel) | GraalVM native binary |
+| 3 | 00:02.855 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_royvanrijn.java)| 21.0.1-graal | [Roy van Rijn](https://github.com/royvanrijn) | GraalVM native binary |
 |   | 00:03.258 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_merykitty.java)| 21.0.1-open | [Quan Anh Mai](https://github.com/merykitty) |  |
 |   | 00:03.321 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_artsiomkorzun.java)| 21.0.1-graal | [Artsiom Korzun](https://github.com/artsiomkorzun) |  |
 |   | 00:03.539 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_mtopolnik.java)| 21.0.1-graal | [Marko Topolnik](https://github.com/mtopolnik) |  |
@@ -51,9 +51,11 @@ These are the results from running all entries into the challenge on eight cores
 |   | 00:04.823 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_JamalMulla.java)| 21.0.1-graal | [Jamal Mulla](https://github.com/JamalMulla) |  |
 |   | 00:04.959 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_yavuztas.java)| 21.0.1-graal | [Yavuz Tas](https://github.com/yavuztas) |  |
 |   | 00:04.996 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_ebarlas.java)| 21.0.1-graal | [Elliot Barlas](https://github.com/ebarlas) |  |
+|   | 00:05.218 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_iziamos.java)| 21.0.1-open | [John Ziamos](https://github.com/iziamos) |  |
 |   | 00:05.478 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_obourgain.java)| 21.0.1-open | [Olivier Bourgain](https://github.com/obourgain) |  |
 |   | 00:05.979 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_spullara.java)| 21.0.1-graal | [Sam Pullara](https://github.com/spullara) |  |
 |   | 00:06.166 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_isolgpus.java)| 21.0.1-open | [Jamie Stansfield](https://github.com/isolgpus) |  |
+|   | 00:06.576 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_asun.java)| 21.0.1-open | [Alan Sun](https://github.com/asun) |  |
 |   | 00:06.715 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_algirdasrascius.java)| 21.0.1-open | [Algirdas Raščius](https://github.com/algirdasrascius) |  |
 |   | 00:07.730 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_jotschi.java)| 21.0.1-open | [Johannes Schüth](https://github.com/jotschi) |  |
 |   | 00:07.843 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_zerninv.java)| 21.0.1-open | [zerninv](https://github.com/zerninv) |  |
@@ -65,25 +67,25 @@ These are the results from running all entries into the challenge on eight cores
 |   | 00:08.517 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_ags313.java)| 21.0.1-graal | [ags](https://github.com/ags313) |  |
 |   | 00:08.892 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_fatroom.java)| 21.0.1-open | [Roman Romanchuk](https://github.com/fatroom) |  |
 |   | 00:09.020 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_yemreinci.java)| 21.0.1-open | [yemreinci](https://github.com/yemreinci) |  |
-|   | 00:09.046 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_iziamos.java)| 21.0.1-open | [John Ziamos](https://github.com/iziamos) |  |
 |   | 00:09.071 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_gabrielreid.java)| 21.0.1-open | [Gabriel Reid](https://github.com/gabrielreid) |  |
 |   | 00:09.117 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_kuduwa-keshavram.java)| 21.0.1-graal | [Keshavram Kuduwa](https://github.com/kuduwa-keshavram) |  |
 |   | 00:09.352 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_filiphr.java)| 21.0.1-graal | [Filip Hrisafov](https://github.com/filiphr) |  |
 |   | 00:09.867 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_ricardopieper.java)| 21.0.1-graal | [Ricardo Pieper](https://github.com/ricardopieper) |  |
 |   | 00:10.127 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_artpar.java)| 21.0.1-open | [Parth Mudgal](https://github.com/artpar) |  |
+|   | 00:10.553 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_C5H12O5.java)| 21.0.1-graal | [Xylitol](https://github.com/C5H12O5) |  |
 |   | 00:10.949 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_roman-r-m.java)| 21.0.1-graal | [Roman Musin](https://github.com/roman-r-m) |  |
 |   | 00:10.473 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_raipc.java)| 21.0.1-open | [Anton Rybochkin](https://github.com/raipc) |  |
-|   | 00:10.642 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_asun.java)| 21.0.1-open | [Alan Sun](https://github.com/asun) |  |
 |   | 00:11.119 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_lawrey.java)| 21.0.1-open | [lawrey](https://github.com/lawrey) |  |
 |   | 00:11.167 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_palmr.java)| 21.0.1-open | [Nick Palmer](https://github.com/palmr) |  |
+|   | 00:11.405 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_imrafaelmerino.java)| 21.0.1-graal | [Rafael Merino García](https://github.com/imrafaelmerino) |  |
 |   | 00:11.805 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_coolmineman.java)| 21.0.1-graal | [Cool_Mineman](https://github.com/coolmineman) |  |
 |   | 00:11.934 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_arjenvaneerde.java)| 21.0.1-open | [arjenvaneerde](https://github.com/arjenvaneerde) |  |
 |   | 00:11.987 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_flippingbits.java)| 21.0.1-graal | [Stefan Sprenger](https://github.com/flippingbits) |  |
 |   | 00:12.220 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_richardstartin.java)| 21.0.1-open | [Richard Startin](https://github.com/richardstartin) |  |
-|   | 00:12.471 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_SamuelYvon.java)| 21.0.1-graal | [Samuel Yvon](https://github.com/SamuelYvon) |  |
-|   | 00:12.557 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_imrafaelmerino.java)| 21.0.1-graal | [Rafael Merino García](https://github.com/imrafaelmerino) |  |
+|   | 00:12.495 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_SamuelYvon.java)| 21.0.1-graal | [Samuel Yvon](https://github.com/SamuelYvon) | GraalVM native binary |
 |   | 00:12.565 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_japplis.java)| 21.0.1-open | [Anthony Goubard](https://github.com/japplis) |  |
 |   | 00:12.568 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_MeanderingProgrammer.java)| 21.0.1-graal | [Vlad](https://github.com/MeanderingProgrammer) |  |
+|   | 00:13.013 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_thanhtrinity.java)| 21.0.1-graal | [Thanh Duong](https://github.com/thanhtrinity) |  |
 |   | 00:13.148 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_charlibot.java)| 21.0.1-open | [Charlie Evans](https://github.com/charlibot) |  |
 |   | 00:13.623 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_phd3.java)| 21.0.1-open | [Pratham](https://github.com/phd3) |  |
 |   | 00:13.817 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_entangled90.java)| 21.0.1-open | [Carlo](https://github.com/entangled90) |  |
@@ -91,13 +93,13 @@ These are the results from running all entries into the challenge on eight cores
 |   | 00:14.867 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_berry120.java)| 21.0.1-open | [Michael Berry](https://github.com/berry120) |  |
 |   | 00:15.662 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_semotpan.java)| 21.0.1-open | [Serghei Motpan](https://github.com/semotpan) |  |
 |   | 00:15.752 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_jbachorik.java)| 21.0.1-tem | [Jaroslav Bachorik](https://github.com/jbachorik) |  |
+|   | 00:16.379 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_ianopolous.java)| 21.0.1-open | [Dr Ian Preston](https://github.com/ianopolous) |  |
 |   | 00:17.490 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_kgeri.java)| 21.0.1-open | [Gergely Kiss](https://github.com/kgeri) |  |
 |   | 00:17.815 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_hallvard.java)| 21.0.1-open | [Hallvard Trætteberg](https://github.com/hallvard) |  |
 |   | 00:18.251 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_seijikun.java)| 21.0.1-graal | [Markus Ebner](https://github.com/seijikun) |  |
 |   | 00:18.448 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_moysesb.java)| 21.0.1-open | [Moysés Borges Furtado](https://github.com/moysesb) |  |
 |   | 00:18.771 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_davecom.java)| 21.0.1-graal | [David Kopec](https://github.com/davecom) |  |
 |   | 00:19.357 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_truelive.java)| 21.0.1-graalce | [Roman Schweitzer](https://github.com/truelive) |  |
-|   | 00:20.095 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_C5H12O5.java)| 21.0.1-graal | [Xylitol](https://github.com/C5H12O5) |  |
 |   | 00:21.989 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_couragelee.java)| 21.0.1-open | [couragelee](https://github.com/couragelee) |  |
 |   | 00:22.457 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_rby.java)| 21.0.1-open | [Ramzi Ben Yahya](https://github.com/rby) |  |
 |   | 00:24.528 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_gnabyl.java)| 21.0.1-open | [Bang NGUYEN](https://github.com/gnabyl) |  |
diff --git a/calculate_average_ianopolous.sh b/calculate_average_ianopolous.sh
index 5f0f23d..5f0f23d 100644..100755
--- a/calculate_average_ianopolous.sh
+++ b/calculate_average_ianopolous.sh
diff --git a/src/main/java/dev/morling/onebrc/CalculateAverage_abeobk.java b/src/main/java/dev/morling/onebrc/CalculateAverage_abeobk.java
index 8d261ef..9d0027c 100644
--- a/src/main/java/dev/morling/onebrc/CalculateAverage_abeobk.java
+++ b/src/main/java/dev/morling/onebrc/CalculateAverage_abeobk.java
@@ -14,217 +14,217 @@
  *  limitations under the License.
  */
 
- package dev.morling.onebrc;
-
- import java.io.IOException;
- import java.lang.foreign.Arena;
- import java.lang.reflect.Field;
- import java.nio.channels.FileChannel;
- import java.nio.channels.FileChannel.MapMode;
- import java.nio.charset.StandardCharsets;
- import java.nio.file.Path;
- import java.nio.file.StandardOpenOption;
- import java.util.TreeMap;
- import sun.misc.Unsafe;
- 
- public class CalculateAverage_abeobk {
-     private static final String FILE = "./measurements.txt";
-     private static final int BUCKET_SIZE = 1 << 16;
-     private static final int BUCKET_MASK = BUCKET_SIZE - 1;
-     private static final int MAX_STR_LEN = 100;
-     private static final Unsafe UNSAFE = initUnsafe();
-     private static final long[] HASH_MASKS = new long[]{
-             0x0L,
-             0xffL,
-             0xffffL,
-             0xffffffL,
-             0xffffffffL,
-             0xffffffffffL,
-             0xffffffffffffL,
-             0xffffffffffffffL,
-             0xffffffffffffffffL, };
- 
-     private static Unsafe initUnsafe() {
-         try {
-             Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
-             theUnsafe.setAccessible(true);
-             return (Unsafe) theUnsafe.get(Unsafe.class);
-         }
-         catch (Exception ex) {
-             throw new RuntimeException();
-         }
-     }
- 
-     // stat
-     private static class Stat {
-         private int min;
-         private int max;
-         private long sum;
-         private int count;
- 
-         Stat(int v) {
-             sum = min = max = v;
-             count = 1;
-         }
- 
-         void add(int val) {
-             min = Math.min(val, min);
-             max = Math.max(val, max);
-             sum += val;
-             count++;
-         }
- 
-         void merge(Stat other) {
-             min = Math.min(other.min, min);
-             max = Math.max(other.max, max);
-             sum += other.sum;
-             count += other.count;
-         }
- 
-         public String toString() {
-             return String.format("%.1f/%.1f/%.1f", min * 0.1, sum * 0.1 / count, max * 0.1);
-         }
-     }
- 
-     static class Node {
-         long addr;
-         int keylen;
-         int hash;
-         long[] buf = new long[13];
-         Stat stat;
- 
-         String key() {
-             byte[] buf = new byte[MAX_STR_LEN];
-             UNSAFE.copyMemory(null, addr, buf, Unsafe.ARRAY_BYTE_BASE_OFFSET, keylen);
-             return new String(buf, 0, keylen, StandardCharsets.UTF_8);
-         }
- 
-         Node(long a, int kl, int h, int v, long[] b) {
-             stat = new Stat(v);
-             addr = a;
-             keylen = kl;
-             hash = h;
-             System.arraycopy(b, 0, buf, 0, Math.ceilDiv(kl, 8));
-         }
- 
-         boolean contentEquals(final long[] other_buf) {
-             int k = keylen / 8;
-             int r = keylen % 8;
-             // Since the city name is most likely shorter than 16 characters
-             // this should be faster than typical conditional checks
-             long sum = 0;
-             for (int i = 0; i < k; i++) {
-                 sum += buf[i] ^ other_buf[i];
-             }
-             sum += (buf[k] ^ other_buf[k]) & HASH_MASKS[r];
-             return sum == 0;
-         }
-     }
- 
-     // split into chunks
-     static long[] slice(long start_addr, long end_addr, long chunk_size, int cpu_cnt) {
-         long[] ptrs = new long[cpu_cnt + 1];
-         ptrs[0] = start_addr;
-         for (int i = 1; i < cpu_cnt; i++) {
-             long addr = start_addr + i * chunk_size;
-             while (addr < end_addr && UNSAFE.getByte(addr++) != '\n')
-                 ;
-             ptrs[i] = Math.min(addr, end_addr);
-         }
-         ptrs[cpu_cnt] = end_addr;
-         return ptrs;
-     }
- 
-     public static void main(String[] args) throws InterruptedException, IOException {
-         int cpu_cnt = Runtime.getRuntime().availableProcessors() / 2;
-         try (var file = FileChannel.open(Path.of(FILE), StandardOpenOption.READ)) {
-             long start_addr = file.map(MapMode.READ_ONLY, 0, file.size(), Arena.global()).address();
-             long file_size = file.size();
-             long end_addr = start_addr + file_size;
-             long chunk_size = Math.ceilDiv(file_size, cpu_cnt);
- 
-             // processing
-             var threads = new Thread[cpu_cnt];
-             var maps = new Node[cpu_cnt][];
-             var ptrs = slice(start_addr, end_addr, chunk_size, cpu_cnt);
- 
-             for (int i = 0; i < cpu_cnt; i++) {
-                 int thread_id = i;
-                 long start = ptrs[i];
-                 long end = ptrs[i + 1];
-                 maps[i] = new Node[BUCKET_SIZE + 16]; // extra space for collisions
- 
-                 (threads[i] = new Thread(() -> {
-                     long addr = start;
-                     var map = maps[thread_id];
-                     long[] buf = new long[13];
-                     // parse loop
-                     while (addr < end) {
-                         int idx = 0;
-                         long hash = 0;
-                         long word = 0;
-                         long row_addr = addr;
-                         int semi_pos = 8;
-                         while (semi_pos == 8) {
-                             word = UNSAFE.getLong(addr);
-                             buf[idx++] = word;
-                             // idea from thomaswue & royvanrijn
-                             long xor_semi = word ^ 0x3b3b3b3b3b3b3b3bL; // xor with ;;;;;;;;
-                             long semipos_code = (xor_semi - 0x0101010101010101L) & ~xor_semi & 0x8080808080808080L;
-                             semi_pos = Long.numberOfTrailingZeros(semipos_code) >>> 3;
-                             addr += semi_pos;
-                             hash ^= word & HASH_MASKS[semi_pos];
-                         }
- 
-                         int hash32 = (int) (hash ^ (hash >>> 31));
-                         int keylen = (int) (addr - row_addr);
- 
-                         // great idea from merykitty (Quan Anh Mai)
-                         long num_word = UNSAFE.getLong(++addr);
-                         int dot_pos = Long.numberOfTrailingZeros(~num_word & 0x10101000);
-                         addr += (dot_pos >>> 3) + 3;
- 
-                         int shift = 28 - dot_pos;
-                         long signed = (~num_word << 59) >> 63;
-                         long dsmask = ~(signed & 0xFF);
-                         long digits = ((num_word & dsmask) << shift) & 0x0F000F0F00L;
-                         long abs_val = ((digits * 0x640a0001) >>> 32) & 0x3FF;
-                         int val = (int) ((abs_val ^ signed) - signed);
- 
-                         int bucket = (hash32 & BUCKET_MASK);
-                         while (true) {
-                             var node = map[bucket];
-                             if (node == null) {
-                                 map[bucket] = new Node(row_addr, keylen, hash32, val, buf);
-                                 break;
-                             }
-                             if (node.keylen == keylen && node.hash == hash32 && node.contentEquals(buf)) {
-                                 node.stat.add(val);
-                                 break;
-                             }
-                             bucket++;
-                         }
-                     }
-                 })).start();
-             }
- 
-             // join all
-             for (var thread : threads)
-                 thread.join();
- 
-             // collect results
-             TreeMap<String, Stat> ms = new TreeMap<>();
-             for (var map : maps) {
-                 for (var node : map) {
-                     if (node == null)
-                         continue;
-                     var stat = ms.putIfAbsent(node.key(), node.stat);
-                     if (stat != null)
-                         stat.merge(node.stat);
-                 }
-             }
- 
-             System.out.println(ms);
-         }
-     }
- }
\ No newline at end of file
+package dev.morling.onebrc;
+
+import java.io.IOException;
+import java.lang.foreign.Arena;
+import java.lang.reflect.Field;
+import java.nio.channels.FileChannel;
+import java.nio.channels.FileChannel.MapMode;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+import java.util.TreeMap;
+import sun.misc.Unsafe;
+
+public class CalculateAverage_abeobk {
+    private static final String FILE = "./measurements.txt";
+    private static final int BUCKET_SIZE = 1 << 16;
+    private static final int BUCKET_MASK = BUCKET_SIZE - 1;
+    private static final int MAX_STR_LEN = 100;
+    private static final Unsafe UNSAFE = initUnsafe();
+    private static final long[] HASH_MASKS = new long[]{
+            0x0L,
+            0xffL,
+            0xffffL,
+            0xffffffL,
+            0xffffffffL,
+            0xffffffffffL,
+            0xffffffffffffL,
+            0xffffffffffffffL,
+            0xffffffffffffffffL, };
+
+    private static Unsafe initUnsafe() {
+        try {
+            Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
+            theUnsafe.setAccessible(true);
+            return (Unsafe) theUnsafe.get(Unsafe.class);
+        }
+        catch (Exception ex) {
+            throw new RuntimeException();
+        }
+    }
+
+    // stat
+    private static class Stat {
+        private int min;
+        private int max;
+        private long sum;
+        private int count;
+
+        Stat(int v) {
+            sum = min = max = v;
+            count = 1;
+        }
+
+        void add(int val) {
+            min = Math.min(val, min);
+            max = Math.max(val, max);
+            sum += val;
+            count++;
+        }
+
+        void merge(Stat other) {
+            min = Math.min(other.min, min);
+            max = Math.max(other.max, max);
+            sum += other.sum;
+            count += other.count;
+        }
+
+        public String toString() {
+            return String.format("%.1f/%.1f/%.1f", min * 0.1, sum * 0.1 / count, max * 0.1);
+        }
+    }
+
+    static class Node {
+        long addr;
+        int keylen;
+        int hash;
+        long[] buf = new long[13];
+        Stat stat;
+
+        String key() {
+            byte[] buf = new byte[MAX_STR_LEN];
+            UNSAFE.copyMemory(null, addr, buf, Unsafe.ARRAY_BYTE_BASE_OFFSET, keylen);
+            return new String(buf, 0, keylen, StandardCharsets.UTF_8);
+        }
+
+        Node(long a, int kl, int h, int v, long[] b) {
+            stat = new Stat(v);
+            addr = a;
+            keylen = kl;
+            hash = h;
+            System.arraycopy(b, 0, buf, 0, Math.ceilDiv(kl, 8));
+        }
+
+        boolean contentEquals(final long[] other_buf) {
+            int k = keylen / 8;
+            int r = keylen % 8;
+            // Since the city name is most likely shorter than 16 characters
+            // this should be faster than typical conditional checks
+            long sum = 0;
+            for (int i = 0; i < k; i++) {
+                sum += buf[i] ^ other_buf[i];
+            }
+            sum += (buf[k] ^ other_buf[k]) & HASH_MASKS[r];
+            return sum == 0;
+        }
+    }
+
+    // split into chunks
+    static long[] slice(long start_addr, long end_addr, long chunk_size, int cpu_cnt) {
+        long[] ptrs = new long[cpu_cnt + 1];
+        ptrs[0] = start_addr;
+        for (int i = 1; i < cpu_cnt; i++) {
+            long addr = start_addr + i * chunk_size;
+            while (addr < end_addr && UNSAFE.getByte(addr++) != '\n')
+                ;
+            ptrs[i] = Math.min(addr, end_addr);
+        }
+        ptrs[cpu_cnt] = end_addr;
+        return ptrs;
+    }
+
+    public static void main(String[] args) throws InterruptedException, IOException {
+        int cpu_cnt = Runtime.getRuntime().availableProcessors() / 2;
+        try (var file = FileChannel.open(Path.of(FILE), StandardOpenOption.READ)) {
+            long start_addr = file.map(MapMode.READ_ONLY, 0, file.size(), Arena.global()).address();
+            long file_size = file.size();
+            long end_addr = start_addr + file_size;
+            long chunk_size = Math.ceilDiv(file_size, cpu_cnt);
+
+            // processing
+            var threads = new Thread[cpu_cnt];
+            var maps = new Node[cpu_cnt][];
+            var ptrs = slice(start_addr, end_addr, chunk_size, cpu_cnt);
+
+            for (int i = 0; i < cpu_cnt; i++) {
+                int thread_id = i;
+                long start = ptrs[i];
+                long end = ptrs[i + 1];
+                maps[i] = new Node[BUCKET_SIZE + 16]; // extra space for collisions
+
+                (threads[i] = new Thread(() -> {
+                    long addr = start;
+                    var map = maps[thread_id];
+                    long[] buf = new long[13];
+                    // parse loop
+                    while (addr < end) {
+                        int idx = 0;
+                        long hash = 0;
+                        long word = 0;
+                        long row_addr = addr;
+                        int semi_pos = 8;
+                        while (semi_pos == 8) {
+                            word = UNSAFE.getLong(addr);
+                            buf[idx++] = word;
+                            // idea from thomaswue & royvanrijn
+                            long xor_semi = word ^ 0x3b3b3b3b3b3b3b3bL; // xor with ;;;;;;;;
+                            long semipos_code = (xor_semi - 0x0101010101010101L) & ~xor_semi & 0x8080808080808080L;
+                            semi_pos = Long.numberOfTrailingZeros(semipos_code) >>> 3;
+                            addr += semi_pos;
+                            hash ^= word & HASH_MASKS[semi_pos];
+                        }
+
+                        int hash32 = (int) (hash ^ (hash >>> 31));
+                        int keylen = (int) (addr - row_addr);
+
+                        // great idea from merykitty (Quan Anh Mai)
+                        long num_word = UNSAFE.getLong(++addr);
+                        int dot_pos = Long.numberOfTrailingZeros(~num_word & 0x10101000);
+                        addr += (dot_pos >>> 3) + 3;
+
+                        int shift = 28 - dot_pos;
+                        long signed = (~num_word << 59) >> 63;
+                        long dsmask = ~(signed & 0xFF);
+                        long digits = ((num_word & dsmask) << shift) & 0x0F000F0F00L;
+                        long abs_val = ((digits * 0x640a0001) >>> 32) & 0x3FF;
+                        int val = (int) ((abs_val ^ signed) - signed);
+
+                        int bucket = (hash32 & BUCKET_MASK);
+                        while (true) {
+                            var node = map[bucket];
+                            if (node == null) {
+                                map[bucket] = new Node(row_addr, keylen, hash32, val, buf);
+                                break;
+                            }
+                            if (node.keylen == keylen && node.hash == hash32 && node.contentEquals(buf)) {
+                                node.stat.add(val);
+                                break;
+                            }
+                            bucket++;
+                        }
+                    }
+                })).start();
+            }
+
+            // join all
+            for (var thread : threads)
+                thread.join();
+
+            // collect results
+            TreeMap<String, Stat> ms = new TreeMap<>();
+            for (var map : maps) {
+                for (var node : map) {
+                    if (node == null)
+                        continue;
+                    var stat = ms.putIfAbsent(node.key(), node.stat);
+                    if (stat != null)
+                        stat.merge(node.stat);
+                }
+            }
+
+            System.out.println(ms);
+        }
+    }
+}
\ No newline at end of file