diff --git a/case.cc b/case.cc
index 83502e1..c35f2e6 100644
--- a/case.cc
+++ b/case.cc
@@ -6,6 +6,14 @@ bool check_case(int head, uint32_t range);
 void build_base_range(std::vector<uint32_t> &base_range);
 void gen_range(std::vector<uint32_t> &release, int n1, int n2, int n3, int n4);
 
+inline int binary_num(uint32_t binary, int length) { // get number of non-zero bit
+    int num = 0;
+    for (int i = 0; i < length; ++i) {
+        num += int((binary >> i) & 0x1);
+    }
+    return num;
+}
+
 void find_all_case(std::vector<uint64_t> *all_case) {
     all_case->clear();
     std::vector<uint32_t> base_range;
diff --git a/common.cc b/common.cc
index a009e0c..b30563c 100644
--- a/common.cc
+++ b/common.cc
@@ -1,15 +1,5 @@
 #include "common.h"
 
-//inline int binary_num(uint32_t binary, int length) { // get number of non-zero bit
-int binary_num(uint32_t binary, int length) { // get number of non-zero bit
-    int num = 0;
-    for (int i = 0; i < length; ++i) {
-        num += int((binary >> i) & 0x1);
-    }
-    return num;
-}
-
-//inline void binary_reverse(uint32_t &range) { // reverse binary every 2 bits
 void binary_reverse(uint32_t &range) { // reverse binary every 2 bits
     range = ((range << 16) & 0xFFFF0000) | ((range >> 16) & 0x0000FFFF);
     range = ((range << 8) & 0xFF00FF00) | ((range >> 8) & 0x00FF00FF);
@@ -17,7 +7,6 @@ void binary_reverse(uint32_t &range) { // reverse binary every 2 bits
     range = ((range << 2) & 0xCCCCCCCC) | ((range >> 2) & 0x33333333);
 }
 
-//inline void binary_to_str(uint64_t binary, char *string) {
 void binary_to_str(uint64_t binary, char *string) {
     for (int i = 0; i < 9; ++i, ++string) { // only read low 9 * 4 bits
         *string = int8_t(binary >> (8 - i) * 4 & 0xF);
diff --git a/common.h b/common.h
index 0b2ad51..dfbca11 100644
--- a/common.h
+++ b/common.h
@@ -4,7 +4,6 @@
 #include <cstdint>
 
 void binary_reverse(uint32_t &range);
-int binary_num(uint32_t binary, int length);
 void binary_to_str(uint64_t binary, char *string);
 
 #endif
diff --git a/klotski b/klotski
deleted file mode 100755
index 0a56628..0000000
Binary files a/klotski and /dev/null differ