diff --git a/klotski/all_cases.cc b/klotski/all_cases.cc
index 3b2ee2f..238ae52 100644
--- a/klotski/all_cases.cc
+++ b/klotski/all_cases.cc
@@ -93,6 +93,30 @@ void AllCases::build_basic_ranges() { // build basic ranges
     }
 }
 
+void AllCases::find_all_cases() { // find all valid cases
+    get_basic_ranges(); // ensure basic ranges exist
+    for (uint32_t head = 0; head < 16; ++head) { // address of 2x2 block
+        if ((head & 0b11) == 0b11) {
+            continue; // invalid 2x2 address
+        }
+        for (uint32_t range : basic_ranges) { // check base on 2x2 address and range
+            if (Common::check_case(head, range)) {
+                all_cases[head].emplace_back(Common::range_reverse(range)); // found valid case
+            }
+        }
+    }
+}
+
 const std::vector<uint32_t>* AllCases::get_basic_ranges() {
+    if (basic_ranges.empty()) {
+        build_basic_ranges(); // basic ranges initialize
+    }
     return &basic_ranges;
 }
+
+const std::vector<uint32_t> (*AllCases::get_all_cases())[16] {
+    if (all_cases->empty()) {
+        find_all_cases(); // all cases initialize
+    }
+    return &all_cases;
+}
diff --git a/klotski/all_cases.h b/klotski/all_cases.h
index e2ada86..98084fc 100644
--- a/klotski/all_cases.h
+++ b/klotski/all_cases.h
@@ -6,16 +6,14 @@
 class AllCases {
 public:
 //    AllCases() {}
-//    void find_all_cases();
-
-    void build_basic_ranges();
-
     const std::vector<uint32_t>* get_basic_ranges();
+    const std::vector<uint32_t> (*get_all_cases())[16];
 
 private:
-//    std::vector<uint32_t> all_cases[16];
     std::vector<uint32_t> basic_ranges;
+    std::vector<uint32_t> all_cases[16];
 
-//    void load_basic_ranges();
+    void find_all_cases();
+    void build_basic_ranges();
     void generate_ranges(int n1, int n2, int n3, int n4);
 };
diff --git a/klotski/main.cc b/klotski/main.cc
index 52e02e4..04f1d51 100644
--- a/klotski/main.cc
+++ b/klotski/main.cc
@@ -4,10 +4,12 @@
 int main() {
 
     auto a = AllCases();
-    a.build_basic_ranges();
 
-    auto br = a.get_basic_ranges();
-    std::cout << br->size() << std::endl;
+    std::cout << "basic range size: " << a.get_basic_ranges()->size() << std::endl;
+
+    for (const auto &temp : *a.get_all_cases()) {
+        std::cout << temp.size() << std::endl;
+    }
 
     return 0;
 }