diff --git a/src/core/core.cc b/src/core/core.cc
index 6f2709b..1c54c1b 100644
--- a/src/core/core.cc
+++ b/src/core/core.cc
@@ -170,13 +170,9 @@ void Core::next_step(uint64_t code, uint64_t mask) { // search next step cases
                 continue; // B_space or B_fill
         }
         if (cache_size != 1) { // found one or more next cases
-
-            // TODO: try to send multi-items data
-//            for (int i = 1; i < cache_size; ++i) {
-//                release(cache[i].code, cache[i].mask); // release next cases
-//            }
-            release(cache, cache_size);
-
+            for (int i = 1; i < cache_size; ++i) {
+                release(cache[i].code, cache[i].mask); // release next cases
+            }
             cache_size = 1; // reset cache size
         }
     }
diff --git a/src/core/core.h b/src/core/core.h
index f84c73a..d6e1f82 100644
--- a/src/core/core.h
+++ b/src/core/core.h
@@ -11,7 +11,12 @@
 
 class Core {
 public:
+    typedef std::function<void(uint64_t, uint64_t)> release_t;
 
+    void next_step(uint64_t code, uint64_t mask);
+    explicit Core(release_t release_func) : release(std::move(release_func)) {}
+
+private:
     struct cache_t {
         uint64_t code; // case raw code
         uint64_t mask; // only 000 or 111
@@ -19,14 +24,6 @@ public:
         int addr; // (0 ~ 19) * 3
     };
 
-//    typedef std::function<void(uint64_t, uint64_t)> release_t;
-    typedef std::function<void(cache_t*, int)> release_t;
-
-    void next_step(uint64_t code, uint64_t mask);
-    explicit Core(release_t release_func) : release(std::move(release_func)) {}
-
-private:
-
     int cache_size = 1;
     cache_t cache[16] = {0};
     release_t release; // release code and mask
diff --git a/src/fast_cal/fast_cal.cc b/src/fast_cal/fast_cal.cc
index 682a8e8..5842549 100644
--- a/src/fast_cal/fast_cal.cc
+++ b/src/fast_cal/fast_cal.cc
@@ -8,12 +8,11 @@
 
 void FastCal::fast_cal(uint64_t code) {
 
-    std::cout << RawCode(code).dump_case() << std::endl;
+//    std::cout << RawCode(code).dump_case() << std::endl;
 
     auto core = Core(
-        [this](auto &&p1, auto &&p2) {
-//            add_new_case(std::forward<decltype(p1)>(p1), std::forward<decltype(p2)>(p2));
-            add_new_case_demo(std::forward<decltype(p1)>(p1), std::forward<decltype(p2)>(p2));
+        [this](auto &&code, auto &&mask) { // lambda as function pointer
+            add_new_case(std::forward<decltype(code)>(code), std::forward<decltype(mask)>(mask));
         }
     );
 
@@ -29,10 +28,10 @@ void FastCal::fast_cal(uint64_t code) {
 
     while (!cache.empty()) {
 
-        // break check point
+        /// break check point
+
         if (((cache.front()->code >> (3 * 0xD)) & 0b111) == B_2x2) {
             std::cout << "Resolved" << std::endl;
-//            std::cout << RawCode(cache.front()->code).dump_case() << std::endl;
             break;
         }
 
@@ -67,27 +66,3 @@ void FastCal::add_new_case(uint64_t code, uint64_t mask) {
     cache.emplace(&cases[code]);
 
 }
-
-void FastCal::add_new_case_demo(Core::cache_t *cache_dat, int cache_size) {
-
-    for (int i = 1; i < cache_size; ++i) {
-        uint64_t code = cache_dat[i].code;
-        uint64_t mask = cache_dat[i].mask;
-
-        auto exist_case = cases.find(code);
-        if (exist_case != cases.end()) {
-            exist_case->second.mask |= mask;
-            continue;
-        }
-
-        cases[code] = fast_cal_t {
-            .code = code,
-            .mask = mask,
-            .last = cache.front(),
-        };
-        cache.emplace(&cases[code]);
-
-    }
-
-
-}
diff --git a/src/fast_cal/fast_cal.h b/src/fast_cal/fast_cal.h
index aa2bf73..f8dbc68 100644
--- a/src/fast_cal/fast_cal.h
+++ b/src/fast_cal/fast_cal.h
@@ -18,6 +18,5 @@ public:
     void fast_cal(uint64_t code);
 
     void add_new_case(uint64_t code, uint64_t mask);
-    void add_new_case_demo(Core::cache_t *cache_dat, int cache_size);
 
 };