diff --git a/src/klotski_core/common_code/common_code.cc b/src/klotski_core/common_code/common_code.cc
index 57ceeb6..4736822 100644
--- a/src/klotski_core/common_code/common_code.cc
+++ b/src/klotski_core/common_code/common_code.cc
@@ -21,7 +21,7 @@ CommonCode CommonCode::unsafe_create(uint64_t common_code) noexcept { // create
 
 CommonCode::CommonCode(uint64_t common_code) {
     if (!CommonCode::check(common_code)) { // check input common code
-        throw klotski::CommonCodeException("common code invalid");
+        throw klotski::CommonCodeExp("common code invalid");
     }
     code_ = common_code;
 }
diff --git a/src/klotski_core/common_code/common_code.h b/src/klotski_core/common_code/common_code.h
index 4f7ad87..09da66f 100644
--- a/src/klotski_core/common_code/common_code.h
+++ b/src/klotski_core/common_code/common_code.h
@@ -63,11 +63,11 @@ namespace klotski {
 class RawCode;
 class ShortCode;
 
-class CommonCodeException : public std::runtime_error {
+class CommonCodeExp : public std::runtime_error {
 public:
-    CommonCodeException() : std::runtime_error("invalid common code") {}
-    explicit CommonCodeException(const std::string &msg) : std::runtime_error(msg) {}
-    ~CommonCodeException() noexcept override = default;
+    CommonCodeExp() : std::runtime_error("invalid common code") {}
+    explicit CommonCodeExp(const std::string &msg) : std::runtime_error(msg) {}
+    ~CommonCodeExp() noexcept override = default;
 };
 
 class CommonCode {
diff --git a/src/klotski_core/common_code/serialize.cc b/src/klotski_core/common_code/serialize.cc
index 7e92dcf..fbfadb3 100644
--- a/src/klotski_core/common_code/serialize.cc
+++ b/src/klotski_core/common_code/serialize.cc
@@ -1,7 +1,7 @@
 #include "common_code.h"
 
 using klotski::CommonCode;
-using klotski::CommonCodeException;
+using klotski::CommonCodeExp;
 
 /// -------------------------- CommonCode to String ---------------------------
 
@@ -60,7 +60,7 @@ std::string CommonCode::string_encode(uint64_t common_code, bool shorten) noexce
 uint64_t CommonCode::string_decode(const std::string &common_code) { // convert from (1 ~ 9)-bit string
     /// check string length
     if (common_code.length() > 9 || common_code.empty()) { // check string length
-        throw CommonCodeException("common code should length 1 ~ 9");
+        throw CommonCodeExp("common code should length 1 ~ 9");
     }
 
     /// check every characters
@@ -74,14 +74,14 @@ uint64_t CommonCode::string_decode(const std::string &common_code) { // convert
         } else if (bit >= 'a' && bit <= 'f') { // a ~ f
             result |= (bit - 87);
         } else {
-            throw CommonCodeException("common code with invalid character"); // unknown character
+            throw CommonCodeExp("common code with invalid character"); // unknown character
         }
     }
     result <<= (9 - common_code.length()) * 4; // low-bits fill with zero
 
     /// check whether common code is valid
     if (!CommonCode::check(result)) { // check converted common code
-        throw CommonCodeException("common code invalid");
+        throw CommonCodeExp("common code invalid");
     }
     return result;
 }
diff --git a/src/klotski_core/raw_code/convert.cc b/src/klotski_core/raw_code/convert.cc
index 20f3d89..9bdc2b2 100644
--- a/src/klotski_core/raw_code/convert.cc
+++ b/src/klotski_core/raw_code/convert.cc
@@ -3,7 +3,7 @@
 
 using klotski::RawCode;
 using klotski::CommonCode;
-using klotski::RawCodeException;
+using klotski::RawCodeExp;
 
 /// -------------------------- RawCode to CommonCode --------------------------
 
diff --git a/src/klotski_core/raw_code/raw_code.cc b/src/klotski_core/raw_code/raw_code.cc
index 2c87a1c..14d596c 100644
--- a/src/klotski_core/raw_code/raw_code.cc
+++ b/src/klotski_core/raw_code/raw_code.cc
@@ -19,7 +19,7 @@ RawCode RawCode::unsafe_create(uint64_t raw_code) noexcept { // create without c
 
 RawCode::RawCode(uint64_t raw_code) {
     if (!RawCode::check(raw_code)) { // check input raw code
-        throw klotski::RawCodeException("raw code invalid");
+        throw klotski::RawCodeExp("raw code invalid");
     }
     code_ = raw_code;
 }
diff --git a/src/klotski_core/raw_code/raw_code.h b/src/klotski_core/raw_code/raw_code.h
index 605a912..bd88e5c 100644
--- a/src/klotski_core/raw_code/raw_code.h
+++ b/src/klotski_core/raw_code/raw_code.h
@@ -47,11 +47,11 @@ namespace klotski {
 
 class CommonCode;
 
-class RawCodeException : public std::runtime_error {
+class RawCodeExp : public std::runtime_error {
 public:
-    RawCodeException() : std::runtime_error("invalid raw code") {}
-    explicit RawCodeException(const std::string &msg) : std::runtime_error(msg) {}
-    ~RawCodeException() noexcept override = default;
+    RawCodeExp() : std::runtime_error("invalid raw code") {}
+    explicit RawCodeExp(const std::string &msg) : std::runtime_error(msg) {}
+    ~RawCodeExp() noexcept override = default;
 };
 
 class RawCode {
diff --git a/src/klotski_core/short_code/serialize.cc b/src/klotski_core/short_code/serialize.cc
index e502f15..dacaca9 100644
--- a/src/klotski_core/short_code/serialize.cc
+++ b/src/klotski_core/short_code/serialize.cc
@@ -2,7 +2,7 @@
 #include "serialize_chars.h"
 
 using klotski::ShortCode;
-using klotski::ShortCodeException;
+using klotski::ShortCodeExp;
 
 /// --------------------------- ShortCode to String ---------------------------
 
@@ -42,7 +42,7 @@ std::string ShortCode::string_encode(uint32_t short_code) noexcept { // encode a
 
 uint32_t ShortCode::string_decode(const std::string &short_code) { // 5-bits string decode
     if (short_code.length() != 5) { // check string length
-        throw ShortCodeException("short code should length 5");
+        throw ShortCodeExp("short code should length 5");
     }
     uint64_t result = 0;
     for (auto bit : short_code) {
@@ -51,15 +51,15 @@ uint32_t ShortCode::string_decode(const std::string &short_code) { // 5-bits str
             bit -= 32; // convert to uppercase
         }
         if (bit < '1' || bit > 'Z') { // invalid characters
-            throw ShortCodeException("short code with invalid character");
+            throw ShortCodeExp("short code with invalid character");
         }
         result += (bit = SHORT_CODE_TABLE_REV[bit - 49]); // table convert
         if (bit == -1) { // invalid character
-            throw ShortCodeException("short code with invalid character");
+            throw ShortCodeExp("short code with invalid character");
         }
     }
     if (!ShortCode::check(result)) { // check converted short code
-        throw ShortCodeException("short code invalid");
+        throw ShortCodeExp("short code invalid");
     }
     return result; // apply convert result
 }
diff --git a/src/klotski_core/short_code/short_code.cc b/src/klotski_core/short_code/short_code.cc
index 99df07a..b744bc9 100644
--- a/src/klotski_core/short_code/short_code.cc
+++ b/src/klotski_core/short_code/short_code.cc
@@ -22,7 +22,7 @@ ShortCode ShortCode::unsafe_create(uint32_t short_code) noexcept { // create wit
 
 ShortCode::ShortCode(uint32_t short_code) {
     if (!ShortCode::check(short_code)) { // check input short code
-        throw klotski::ShortCodeException("short code invalid");
+        throw klotski::ShortCodeExp("short code invalid");
     }
     code_ = short_code;
 }
diff --git a/src/klotski_core/short_code/short_code.h b/src/klotski_core/short_code/short_code.h
index 9a69e1b..da139be 100644
--- a/src/klotski_core/short_code/short_code.h
+++ b/src/klotski_core/short_code/short_code.h
@@ -62,11 +62,11 @@ class CommonCode;
 
 const uint32_t SHORT_CODE_LIMIT = 29334498;
 
-class ShortCodeException : public std::runtime_error {
+class ShortCodeExp : public std::runtime_error {
 public:
-    ShortCodeException() : std::runtime_error("invalid short code") {}
-    explicit ShortCodeException(const std::string &msg) : std::runtime_error(msg) {}
-    ~ShortCodeException() noexcept override = default;
+    ShortCodeExp() : std::runtime_error("invalid short code") {}
+    explicit ShortCodeExp(const std::string &msg) : std::runtime_error(msg) {}
+    ~ShortCodeExp() noexcept override = default;
 };
 
 /// For ShortCode, you must choose at least one mode (NORMAL or FAST) to convert, and
diff --git a/test/codec/common_code.cc b/test/codec/common_code.cc
index 169dec3..31b6476 100644
--- a/test/codec/common_code.cc
+++ b/test/codec/common_code.cc
@@ -17,7 +17,7 @@ static inline void SHOULD_PANIC(const std::function<void()> &func) {
     bool panic_flag = false;
     try {
         func();
-    } catch (klotski::CommonCodeException&) {
+    } catch (klotski::CommonCodeExp &) {
         panic_flag = true;
     }
     EXPECT_EQ(panic_flag, true);
diff --git a/test/codec/short_code.cc b/test/codec/short_code.cc
index 6f5df8b..a88635d 100644
--- a/test/codec/short_code.cc
+++ b/test/codec/short_code.cc
@@ -20,7 +20,7 @@ static inline void SHOULD_PANIC(const std::function<void()> &func) {
     bool panic_flag = false;
     try {
         func();
-    } catch (klotski::ShortCodeException&) {
+    } catch (klotski::ShortCodeExp &) {
         panic_flag = true;
     }
     EXPECT_EQ(panic_flag, true);