diff --git a/src/common_code/CMakeLists.txt b/src/common_code/CMakeLists.txt
index 7b6d129..077dcde 100644
--- a/src/common_code/CMakeLists.txt
+++ b/src/common_code/CMakeLists.txt
@@ -1,4 +1,4 @@
 cmake_minimum_required(VERSION 3.0)
 
 add_library(common_code common_code.cc)
-target_link_libraries(common_code utils)
+target_link_libraries(common_code utils raw_code)
diff --git a/src/main.cc b/src/main.cc
index eba3be0..3a0ec5c 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -173,6 +173,9 @@ int main() {
 //        }
 //    }
 
+//    ShortCode::speed_up(ShortCode::FAST);
+    AllCases::build();
+
 //    std::cout << "start benchmark" << std::endl;
     auto start_time = clock();
 
@@ -278,7 +281,20 @@ int main() {
     /// 8146205 -> 4
     /// 29334497 -> 14
 
-    std::cout << std::upper_bound(ALL_CASES_OFFSET, ALL_CASES_OFFSET + 16, 8146203) - ALL_CASES_OFFSET - 1 << std::endl;
+//    std::cout << std::upper_bound(ALL_CASES_OFFSET, ALL_CASES_OFFSET + 16, 8146203) - ALL_CASES_OFFSET - 1 << std::endl;
+
+
+    for (uint32_t i = 0; i < 29334498; ++i) {
+//        std::cout << ShortCode(i).to_common_code().to_string() << std::endl;
+//        if (CommonCode::unsafe_create(ShortCode::fast_decode(i)).to_short_code().unwrap() != i) {
+//        if (ShortCode(i).to_common_code().to_short_code().unwrap() != i) {
+        if (ShortCode::fast_encode(ShortCode::fast_decode(i)) != i) {
+            std::cout << "error" << std::endl;
+        }
+    }
+
+//    printf("%09lX\n", ShortCode::fast_decode(14323231));
+//    std::cout << ShortCode::fast_encode(0x6EC0F8800) << std::endl;
 
     std::cerr << (clock() - start_time) * 1000 / CLOCKS_PER_SEC << "ms" << std::endl;
 //    std::cerr << (clock() - start_time) * 1000000 / CLOCKS_PER_SEC << "us" << std::endl;
diff --git a/src/short_code/data_loader.cc b/src/short_code/data_loader.cc
index 4dddaa5..f367288 100644
--- a/src/short_code/data_loader.cc
+++ b/src/short_code/data_loader.cc
@@ -1,6 +1,7 @@
 #include "all_cases.h"
 #include "short_code.h"
 #include "basic_ranges.h"
+#include "short_code_mark.h"
 
 std::mutex ShortCode::map_building;
 bool ShortCode::fast_mode_available = false;
@@ -50,3 +51,30 @@ void ShortCode::build_mappings() { // build fast search mappings
     }
     map_building.unlock();
 }
+
+#include <iostream>
+#include <algorithm>
+
+uint64_t ShortCode::fast_decode(uint32_t short_code) {
+//    std::cout << "short code: " << short_code << std::endl;
+
+    uint32_t head = std::upper_bound(ALL_CASES_OFFSET, ALL_CASES_OFFSET + 16, short_code) - ALL_CASES_OFFSET - 1;
+//    std::cout << head << std::endl;
+
+//    printf("%08X\n", AllCases::fetch()[head][ short_code - ALL_CASES_OFFSET[head] ]);
+
+    return ((uint64_t)head << 32) | AllCases::fetch()[head][short_code - ALL_CASES_OFFSET[head]];
+}
+
+uint32_t ShortCode::fast_encode(uint64_t common_code) {
+//    printf("common code: %09lX\n", common_code);
+
+    uint32_t head = common_code >> 32;
+
+//    std::cout << "head = " << head << std::endl;
+
+    const auto &a = AllCases::fetch();
+
+    return std::lower_bound(a[head].begin(), a[head].end(), (uint32_t)common_code) - a[head].begin() + ALL_CASES_OFFSET[head];
+
+}
diff --git a/src/short_code/short_code.h b/src/short_code/short_code.h
index c5b79c5..89ed5f9 100644
--- a/src/short_code/short_code.h
+++ b/src/short_code/short_code.h
@@ -34,6 +34,9 @@ public:
         speed_up(mode);
     }
 
+    static uint64_t fast_decode(uint32_t short_code);
+    static uint32_t fast_encode(uint64_t common_code);
+
 private:
     uint32_t code;
     static std::mutex map_building;