diff --git a/src/analyse/analyse.cc b/src/analyse/analyse.cc
index f08aeed..b0361c4 100644
--- a/src/analyse/analyse.cc
+++ b/src/analyse/analyse.cc
@@ -64,7 +64,15 @@ void Analyse::backtrack(const std::vector<uint64_t> &raw_code_list) {
     /// layer init
 //    auto max_step = cases[code].step; // TODO: update max step cal
 //    auto max_step = 81;
-    auto max_step = 14; // TODO: search max_step value
+
+    uint32_t max_step = 0;
+    for (const auto &code : raw_code_list) {
+        // TODO: check whether cases include code
+        if (cases[code].step > max_step) {
+            max_step = cases[code].step;
+        }
+    }
+
     layer_data.resize(max_step + 1);
 
     /// init track begin cases
diff --git a/src/main.cc b/src/main.cc
index ee83fdb..2cf2b77 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -212,14 +212,18 @@ int main() {
 //    };
 //    a.backtrack(raw_codes);
 
+//    std::vector<uint64_t> raw_codes = {
+//        CommonCode("DE77D80").to_raw_code().unwrap(),
+//        CommonCode("DF6DD80").to_raw_code().unwrap(),
+//        CommonCode("DF69730").to_raw_code().unwrap(),
+//        CommonCode("DE76D30").to_raw_code().unwrap(),
+//        CommonCode("D5AF730").to_raw_code().unwrap(),
+//        CommonCode("D5B43BC").to_raw_code().unwrap(),
+//    };
     std::vector<uint64_t> raw_codes = {
-        CommonCode("DE77D80").to_raw_code().unwrap(),
-        CommonCode("DF6DD80").to_raw_code().unwrap(),
-        CommonCode("DF69730").to_raw_code().unwrap(),
-        CommonCode("DE76D30").to_raw_code().unwrap(),
-        CommonCode("D5AF730").to_raw_code().unwrap(),
-        CommonCode("D5B43BC").to_raw_code().unwrap(),
+        CommonCode("EF697C0").to_raw_code().unwrap(),
     };
+    // TODO: FATAL ERROR -> don't using mask in Analyse
     a.backtrack(raw_codes);