diff --git a/Makefile b/Makefile
index 4d98524..c67678d 100644
--- a/Makefile
+++ b/Makefile
@@ -9,18 +9,22 @@ VAL_DIR = validator
 INC_DIR = include
 CHK_DIR = checker
 
+TEST_DIR = src/test
+
 BUILD_DIR = build
 BUILD_TARGET_DIR = $(BUILD_DIR)/target
 BUILD_GEN_DIR = $(BUILD_DIR)/gen
 BUILD_VAL_DIR = $(BUILD_DIR)/val
 BUILD_CHK_DIR = $(BUILD_DIR)/chk
+BUILD_TEST_DIR = $(BUILD_DIR)/test
 LOG_DIR = $(BUILD_DIR)/logs
 
 BUILD_IN_DIR = $(BUILD_DIR)/input
 BUILD_OUT_A_DIR = $(BUILD_DIR)/$(SOL_A)_out
 BUILD_OUT_B_DIR = $(BUILD_DIR)/$(SOL_B)_out
 
-DIRS = $(BUILD_DIR) $(BUILD_TARGET_DIR) $(BUILD_GEN_DIR) $(BUILD_VAL_DIR) $(BUILD_CHK_DIR) $(LOG_DIR) $(BUILD_IN_DIR) $(BUILD_OUT_A_DIR) $(BUILD_OUT_B_DIR)
+
+DIRS = $(BUILD_DIR) $(BUILD_TARGET_DIR) $(BUILD_GEN_DIR) $(BUILD_VAL_DIR) $(BUILD_CHK_DIR) $(LOG_DIR) $(BUILD_IN_DIR) $(BUILD_OUT_A_DIR) $(BUILD_OUT_B_DIR) $(BUILD_TEST_DIR)
 
 CXXFLAGS = -Wall -O2 -std=c++2a 
 GENFLAGS = -N $(N) -M $(M) -pm $(pm)
@@ -56,7 +60,7 @@ pm ?= 0.1
 all: $(SOLS_EXE) $(GENS_EXE) $(VAL_EXE) $(CHK_EXE) $(DIRS)
 	@echo "All executables compiled in $(BUILD_DIR)/"
 
-$(BUILD_DIR) $(BUILD_TARGET_DIR) $(BUILD_GEN_DIR) $(BUILD_VAL_DIR) $(BUILD_CHK_DIR) $(LOG_DIR) $(BUILD_IN_DIR) $(BUILD_OUT_A_DIR) $(BUILD_OUT_B_DIR):
+$(BUILD_DIR) $(BUILD_TARGET_DIR) $(BUILD_GEN_DIR) $(BUILD_VAL_DIR) $(BUILD_CHK_DIR) $(LOG_DIR) $(BUILD_IN_DIR) $(BUILD_OUT_A_DIR) $(BUILD_OUT_B_DIR) $(BUILD_TEST_DIR): 
 	@echo "Creating directory: $@"
 	@mkdir -p $@
 
@@ -83,6 +87,10 @@ $(BUILD_IN_DIR)/input%: $(GEN_TO_RUN) | $(BUILD_IN_DIR)
 	echo "Using Seed: $$SEED" >&2; \
 	./$(GEN_TO_RUN) $(GENFLAGS) "$$SEED" > $@
 
+$(BUILD_TEST_DIR)/%: $(TEST_DIR)/%.cpp | $(BUILD_TEST_DIR)
+	@echo "Compiling Unit Test $< -> $@"
+	$(CXX) $(CXXFLAGS) -I$(INC_DIR) -I$(SRC_DIR)/bsb -o $@ $< -lgtest -lgtest_main -pthread
+
 .PHONY: force
 force:
 
@@ -152,10 +160,18 @@ else
 	@echo "OK: ID=$(id) outputs match!"
 endif
 
+UNIT_TEST_SRCS = $(wildcard $(TEST_DIR)/*.cpp)
+UNIT_TEST_NAMES = $(patsubst $(TEST_DIR)/%.cpp, %, $(UNIT_TEST_SRCS))
 
 .PHONY: test
 test: all $(LOG_DIR) $(BUILD_OUT_A_DIR) $(BUILD_OUT_B_DIR)
-ifeq ($(id),)
+ifdef target
+	@# Case 1: Unit Test 실행 (예: make test target=L33)
+	@echo "--- Running Unit Test Target: [$(target)] ---"
+	@$(MAKE) --no-print-directory $(BUILD_TEST_DIR)/$(target)
+	@echo "-------------------------------------------"
+	@./$(BUILD_TEST_DIR)/$(target)
+else ifeq ($(id),)
 	@echo "--- Running $(TEST_COUNT) tests (Comparing $(SOL_A) vs $(SOL_B)) ---"
 	@echo "--- Using Generator [$(gen)] (N=$(N), M=$(M)) ---"
 	@LOG_FILE=$(LOG_DIR)/test_run_$$(date +%Y%m%d_%H%M%S).log; \
@@ -194,6 +210,10 @@ else
 	@$(MAKE) --no-print-directory check id=$(id) gen=$(gen) SOL_A=$(SOL_A) SOL_B=$(SOL_B) N=$(N) M=$(M)
 endif
 
+.PHONY: $(UNIT_TEST_NAMES)
+$(UNIT_TEST_NAMES):
+	@$(MAKE) --no-print-directory test target=$@
+
 .PHONY: bench
 bench: all
 ifeq ($(id),)
diff --git a/generator/gen1.cpp b/generator/gen1.cpp
index a5cef47..972e9d3 100644
--- a/generator/gen1.cpp
+++ b/generator/gen1.cpp
@@ -20,8 +20,7 @@ int main(int argc, char *argv[]) {
     vector<ll> cnt(n + 1, 0);
     for (ll i = 0; i < m; ++i) {
         ll s = rnd.next(1uLL, n);
-        if(cnt[s] == n-1)
-        {
+        if (cnt[s] == n - 1) {
             i--;
             continue;
         }
diff --git a/src/bsb/bsb.hpp b/src/bsb/L33.hpp
similarity index 94%
rename from src/bsb/bsb.hpp
rename to src/bsb/L33.hpp
index 0c08dc3..368148e 100644
--- a/src/bsb/bsb.hpp
+++ b/src/bsb/L33.hpp
@@ -5,10 +5,10 @@
 #include <boost/heap/fibonacci_heap.hpp>
 #include <cassert>
 #include <cmath>
-#include <iostream>
 #include <list>
 #include <map>
 #include <optional>
+#include <ostream>
 #include <tuple>
 #include <unordered_map>
 #include <utility>
@@ -329,6 +329,26 @@ class L33 {
         return {x, s};
     }
     bool empty() const { return ptr.empty(); }
+
+    void _debug(ostream& os)
+    {
+        os<<"D0: "<<endl;
+        for(auto [B, it_BLIST]:D0)
+        {
+            os<<"["<<B<<"] : ";
+            auto &block = *it_BLIST;
+            for(auto [key, val] : block) os << "(" << key << " : " << val << ") ";
+            os<<endl;
+        }
+        os<<"D1: "<<endl;
+        for(auto [B, it_BLIST]:D1)
+        {
+            os<<"["<<B<<"] : ";
+            auto &block = *it_BLIST;
+            for(auto [key, val] : block) os << "(" << key << " : " << val << ") ";
+            os<<endl;
+        }
+    }
 };
 
 }  // namespace GMS
diff --git a/src/bsb/main.cpp b/src/bsb/main.cpp
index 684e3ef..29169a4 100644
--- a/src/bsb/main.cpp
+++ b/src/bsb/main.cpp
@@ -10,7 +10,7 @@
 #include <utility>
 #include <vector>
 
-#include "bsb.hpp"
+#include "L33.hpp"
 
 using namespace std;
 using namespace GMS;
diff --git a/src/test/L33-test1.cpp b/src/test/L33-test1.cpp
new file mode 100644
index 0000000..2f77c3c
--- /dev/null
+++ b/src/test/L33-test1.cpp
@@ -0,0 +1,93 @@
+#include <gtest/gtest.h>
+
+#include <L33.hpp>
+// #include <limits>
+#include <random>
+
+TEST(L33_test, debug_small) {
+    const unsigned seed = 998244353;
+    const uint N = 10, M = 1, MX = 1e9;
+
+    std::mt19937 gen(seed);
+    std::uniform_int_distribution<int> dis(1, MX);
+
+    GMS::L33<int,int> D(M, MX);
+    std::map<int,int> mp;
+
+    std::vector<int> keys;
+    for(int i=1;i<=N;i++) keys.push_back(i);
+
+    std::shuffle(keys.begin(), keys.end(), gen);
+
+    for(auto key:keys)
+    {
+        int val = dis(gen);
+        std::cerr<<key<<": "<<val<<std::endl;
+
+        mp[val] = key;
+        
+        D.Insert(key, val);
+    }
+
+    std::cerr<<"[!] mp: "<<std::endl;
+    for(auto [val, key] : mp)
+        std::cerr<<key<<": "<<val<<std::endl;
+
+    D._debug(std::cerr);
+    
+    std::cerr<<"[!] D: "<<std::endl;
+    int bef = 0;
+    while(!D.empty())
+    {
+        auto [B, keys] = D.Pull();
+
+        std::cerr<<"[!] new pull; B : "<<B<<" ("<<keys.size()<<')'<<": ";
+        for(auto i:keys) std::cerr<<i<<' ';
+        std::cerr<<std::endl;
+
+        D._debug(std::cerr);
+        
+        EXPECT_LT(bef, B);
+        bef = B;
+        std::cerr<<std::endl;
+    }
+}
+
+TEST(L33_test, DISABLED_emptying_test1) {
+    const double inf = 100;
+    const unsigned seed = 998244353;
+    const uint N = 2328, M = 10, MX = 1e9;
+
+    std::mt19937 gen(seed);
+    std::uniform_int_distribution<int> dis(1, MX);
+    std::uniform_real_distribution<double> valdis(-inf, inf);
+
+    GMS::L33<int, double> D(M, inf);
+
+    std::vector<int> vec;
+    for (int i = 1; i <= N; i++) vec.push_back(i);
+
+    std::shuffle(vec.begin(), vec.end(), gen);
+
+    for (int i = 0; i < N; i++) {
+        D.Insert(vec[i], valdis(gen));
+    }
+
+    int cnt = 0; double bef = -inf;
+
+    while(!D.empty())
+    {
+        auto [B, v] = D.Pull();
+        // std::cerr<<B<<' '<<v.size()<<std::endl;
+        cnt += v.size();
+
+        EXPECT_TRUE(D.empty() || (v.size() == M));
+        EXPECT_LE(bef, B);
+        bef = B;
+    }
+
+    EXPECT_EQ(cnt, N);
+
+    int result = 2 + 2;
+    EXPECT_EQ(result, 4);
+}