diff --git a/src/cli/Cargo.lock b/src/cli/Cargo.lock
index 2c6568e..6a38f39 100644
--- a/src/cli/Cargo.lock
+++ b/src/cli/Cargo.lock
@@ -80,6 +80,7 @@ name = "klotski_ffi"
 version = "0.1.0"
 dependencies = [
  "bindgen",
+ "lazy_static",
 ]
 
 [[package]]
diff --git a/src/cli/src/main.rs b/src/cli/src/main.rs
index 27a3b67..e8c27ac 100644
--- a/src/cli/src/main.rs
+++ b/src/cli/src/main.rs
@@ -36,7 +36,10 @@ fn main() {
     // let r = klotski_ffi::RawCode::from(0x0_E58_FC8_5FF_EBC_4DB).unwrap(); // 4FEA13400
     // let r = klotski_ffi::RawCode::from(0x0_EDB_5FF_EBC_5C8_E58).unwrap(); // 8346AFC00
     // let r = klotski_ffi::RawCode::from(0x0_0F9_1CF_FFA_F17_6DA).unwrap(); // 6BFA47000
-    let r = klotski_ffi::RawCode::from(0x0_603_EDF_5CA_FFF_5E2).unwrap(); // 1A9BF0C00
+    // let r = klotski_ffi::RawCode::from(0x0_603_EDF_5CA_FFF_5E2).unwrap(); // 1A9BF0C00
+
+    // println!("{} => {}", r, r.to_common_code());
+
+    klotski_ffi::demo();
 
-    println!("{} => {}", r, r.to_common_code());
 }
diff --git a/src/rust_ffi/Cargo.lock b/src/rust_ffi/Cargo.lock
index 2c36b2c..7552030 100644
--- a/src/rust_ffi/Cargo.lock
+++ b/src/rust_ffi/Cargo.lock
@@ -73,6 +73,7 @@ name = "klotski_ffi"
 version = "0.1.0"
 dependencies = [
  "bindgen",
+ "lazy_static",
 ]
 
 [[package]]
diff --git a/src/rust_ffi/Cargo.toml b/src/rust_ffi/Cargo.toml
index c9d32c4..e069ea3 100644
--- a/src/rust_ffi/Cargo.toml
+++ b/src/rust_ffi/Cargo.toml
@@ -6,6 +6,7 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+lazy_static = "1.4.0"
 
 [build-dependencies]
 bindgen = "0.63.0"
diff --git a/src/rust_ffi/src/all_cases.rs b/src/rust_ffi/src/all_cases.rs
new file mode 100644
index 0000000..3284961
--- /dev/null
+++ b/src/rust_ffi/src/all_cases.rs
@@ -0,0 +1,52 @@
+use crate::core::Core;
+
+lazy_static! {
+    static ref BASIC_RANGES: Vec<u32> = {
+        unsafe {
+            Core::basic_ranges_build();
+            let mut buffer: Vec<u32> = vec![0; Core::BASIC_RANGES_SIZE as usize];
+            Core::export_basic_ranges(&mut buffer[0]);
+            buffer
+        }
+    };
+}
+
+// struct BasicRange {
+//     data: Option<Vec<u32>>
+// }
+//
+// static mut BASIC_RANGE: BasicRange = BasicRange {
+//     data: None
+// };
+
+// impl BasicRange {
+    // fn fetch(&mut self) -> &Vec<u32> {
+        // match &self.data {
+        //     Some(data) => {
+        //         return data;
+        //     },
+        //     None => (),
+        // };
+
+        // &self.data.unwrap()
+    // }
+
+    // fn build(&mut self) {
+    //     unsafe {
+    //         Core::basic_ranges_build();
+    //         let mut buffer: Vec<u32> = vec![0; Core::BASIC_RANGES_SIZE as usize];
+    //         Core::export_basic_ranges(&mut buffer[0]);
+    //         self.data = Some(buffer);
+    //     }
+    // }
+// }
+
+pub fn demo() {
+
+    println!("demo start");
+
+    println!("{:?}", (*BASIC_RANGES).len());
+
+    println!("demo complete");
+
+}
diff --git a/src/rust_ffi/src/lib.rs b/src/rust_ffi/src/lib.rs
index 2045f9b..c09e78a 100644
--- a/src/rust_ffi/src/lib.rs
+++ b/src/rust_ffi/src/lib.rs
@@ -1,9 +1,15 @@
+#[macro_use]
+extern crate lazy_static;
+
 mod core;
 mod codec;
 mod metadata;
+mod all_cases;
 
 pub use codec::RawCode;
 pub use codec::ShortCode;
 pub use codec::CommonCode;
 
 pub use metadata::load_metadata as metadata;
+
+pub use all_cases::demo;