diff --git a/klotski/CMakeLists.txt b/klotski/CMakeLists.txt
index ba0fdf1..261c9d5 100644
--- a/klotski/CMakeLists.txt
+++ b/klotski/CMakeLists.txt
@@ -1,4 +1,4 @@
 cmake_minimum_required(VERSION 3.0)
 set(CMAKE_CXX_STANDARD 14)
 
-add_executable(klotski main.cc common.cc all_cases.cc)
+add_executable(klotski main.cc common.cc all_cases.cc short_code.cc)
diff --git a/klotski/main.cc b/klotski/main.cc
index ad78994..e17033b 100644
--- a/klotski/main.cc
+++ b/klotski/main.cc
@@ -1,20 +1,31 @@
 #include <iostream>
-#include "all_cases.h"
+//#include "all_cases.h"
+#include "short_code.h"
 
 int main() {
 
 //    auto a = AllCases();
 //    auto a = AllCases(AllCases::InitType::WITH_NOTHING);
 //    auto a = AllCases(AllCases::InitType::WITH_BASIC_RANGES);
-    auto a = AllCases(AllCases::InitType::WITH_ALL_CASES);
+//    auto a = AllCases(AllCases::InitType::WITH_ALL_CASES);
 
-    std::cout << "start get basic ranges" << std::endl;
-    std::cout << "basic range: " << a.get_basic_ranges()->size() << std::endl;
+//    std::cout << "start get basic ranges" << std::endl;
+//    std::cout << "basic range: " << a.get_basic_ranges()->size() << std::endl;
 
-    std::cout << "start get all cases" << std::endl;
-    for (const auto &temp : *a.get_all_cases()) {
-        std::cout << temp.size() << std::endl;
-    }
+//    std::cout << "start get all cases" << std::endl;
+//    for (const auto &temp : *a.get_all_cases()) {
+//        std::cout << temp.size() << std::endl;
+//    }
+
+    auto s = ShortCode();
+
+    s.speed_up();
+    std::cout << s.all_cases_list.size() << std::endl;
+    std::cout << s.all_cases_dict.size() << std::endl;
+
+//    s.speed_up();
+//    std::cout << s.all_cases_list.size() << std::endl;
+//    std::cout << s.all_cases_dict.size() << std::endl;
 
     return 0;
 }
diff --git a/klotski/short_code.cc b/klotski/short_code.cc
new file mode 100644
index 0000000..3e16bf6
--- /dev/null
+++ b/klotski/short_code.cc
@@ -0,0 +1,27 @@
+#include "all_cases.h"
+#include "short_code.h"
+#include "short_code_mark.h"
+
+//#include <iostream>
+
+void ShortCode::build_mapping() { // build fast search mapping
+    auto all = AllCases(AllCases::InitType::WITH_ALL_CASES);
+//    std::cout << "start build" << std::endl;
+    for (int head = 0; head < 16; ++head) {
+        uint64_t prefix = (uint64_t)head << 32;
+        for (const auto &range : (*all.get_all_cases())[head]) {
+            all_cases_list.emplace_back(prefix | range); // short_code => common_code
+        }
+    }
+//    std::cout << "stage-1 ok" << std::endl;
+    for (int n = 0; n < all_cases_list.size(); ++n) {
+        all_cases_dict[all_cases_list[n]] = n; // common_code => short_code
+    }
+//    std::cout << "complete build" << std::endl;
+}
+
+void ShortCode::speed_up() {
+    if (all_cases_list.empty()) {
+        build_mapping();
+    }
+}
diff --git a/klotski/short_code.h b/klotski/short_code.h
new file mode 100644
index 0000000..c5a36ed
--- /dev/null
+++ b/klotski/short_code.h
@@ -0,0 +1,23 @@
+#pragma once
+
+#include <vector>
+#include <cstdint>
+#include <unordered_map>
+
+class ShortCode {
+public:
+
+    std::vector<uint64_t> all_cases_list;                  // short_code -> common_code
+    std::unordered_map<uint64_t, uint32_t> all_cases_dict; // common_code -> short_code
+
+    void speed_up();
+
+
+private:
+//    std::vector<uint64_t> all_cases_list;                  // short_code -> common_code
+//    std::unordered_map<uint64_t, uint32_t> all_cases_dict; // common_code -> short_code
+
+    void build_mapping();
+
+
+};
diff --git a/all_cases/short_code_mark.h b/klotski/short_code_mark.h
similarity index 100%
rename from all_cases/short_code_mark.h
rename to klotski/short_code_mark.h