添加了注释

src/main.cpp

@@ -15,27 +15,27 @@
 #include <unordered_map>
 
 
-// std::string reversedComplement(std::string DNAsequence);
+// 这两个宏用来申请读入和读出流，实现反射并输出日志，获取申请流的变量名字
 
 #define OPEN_IFS_AND_CHECK(file_path,value_name)std::ifstream value_name(file_path);if(value_name.is_open()==false){std::stringstream ss;ss<<"cannot open input file stream : "<<file_path.filename();throw std::runtime_error(ss.str());}else{zt::print("Open input file stream to value ["#value_name"] ok , from [",file_path.filename(),"]\n");}
 
 #define OPEN_OFS_AND_CHECK(file_path,value_name)std::ofstream value_name(file_path);if(value_name.is_open()==false){std::stringstream ss;ss<<"cannot open output file stream : "<<file_path.filename();throw std::runtime_error(ss.str());}else{zt::print("Open output file stream to value ["#value_name"] ok , from [",file_path.filename(),"]\n");}
-
+//最大DNA序列长度
 const size_t MAX_SIZE = 5e4+5;
 
-void reverseComplement(std::array<char, MAX_SIZE> &DNAsequence, const size_t buf_size) 
+void reverseComplement(std::array<char, MAX_SIZE> &DNAsequence, const size_t buf_size) //注意这里使用引用DNA sequence，避免拷贝开销
 {
-    static const std::unordered_map<char, char> complement = {
+    static const std::unordered_map<char, char> complement = { //这里使用查表的方式大大提高CPU速度，因为if分支CPU不容易命中缓存，需要使用查表加速
         {'A', 'T'}, {'a', 'T'},
         {'T', 'A'}, {'t', 'A'},
         {'C', 'G'}, {'c', 'G'},
         {'G', 'C'}, {'g', 'C'}
     };
     
-    std::reverse(DNAsequence.begin(), DNAsequence.begin() + buf_size); 
+    std::reverse(DNAsequence.begin(), DNAsequence.begin() + buf_size); //翻转DNA序列
     
     for (std::remove_const_t<decltype(buf_size)> i = 0; i < buf_size; ++i) { 
-        auto it = complement.find(DNAsequence[i]);
+        auto it = complement.find(DNAsequence[i]);//查表并替换
         if (it != complement.end()) {
             DNAsequence[i] = it->second;
         }
@@ -43,7 +43,7 @@ void reverseComplement(std::array<char, MAX_SIZE> &DNAsequence, const size_t buf
 }
 
 
-class Spent{
+class Spent{ // 使用RAII原理的自动计时器，计算主函数运行时间，析构时自动输出
 private:
     const decltype(std::chrono::system_clock::now()) start;
     const std::string_view name;
@@ -51,7 +51,7 @@ public:
     Spent(std::string_view name)noexcept:start(std::chrono::system_clock::now()),name(name){
         zt::print("[Timer: ",name,"]"," Start timing","\n");
     }
-    ~Spent(){
+    ~Spent()noexcept{
         const auto end = std::chrono::system_clock::now();
         const auto dur = std::chrono::duration_cast<std::chrono::milliseconds> (end-start);
         zt::print("[Timer: ",name,"]"," Stop timing , using ", dur,"\n");
@@ -64,7 +64,7 @@ int main()
         std::ios_base::sync_with_stdio(false); //加了没效果 
         using namespace std;
 
-        Spent all_spent("All spent");
+        Spent all_spent("All spent"); //自动计时器，给主函数计时
         
         std::array<char,MAX_SIZE> buf;
         unsigned long long lines = 0;
@@ -73,7 +73,7 @@ int main()
         
         // ifstream input_file_stream(input_path);
         // ofstream output_file_stream(output_path);
-        OPEN_IFS_AND_CHECK(input_path, input_file_stream)
+        OPEN_IFS_AND_CHECK(input_path, input_file_stream) //创建输入和输出流
         OPEN_OFS_AND_CHECK(output_path, output_file_stream)
 
         // string l = "";
@@ -82,15 +82,15 @@ int main()
         {
             int m = lines%2;
             const auto buf_len = strlen(buf.data());
-            const std::string_view suffix("\n");
+            const std::string_view suffix("\n"); //设置一个每个DNA序列结尾的字符，这里是以\n换行来结尾
             if (m == 1){
                 // output_file_stream << reverseComplement(buf) << endl;
                 reverseComplement(buf,buf_len);
             }
             for(int i=0;i<suffix.size();i++){
-                buf[buf_len+i]=suffix[i];
+                buf[buf_len+i]=suffix[i]; // 将末尾增加字符追加到结尾。注意不能过长超过MAX_SIZE
             }
-            output_file_stream.write(buf.data(), buf_len+suffix.size());
+            output_file_stream.write(buf.data(), buf_len+suffix.size()); // 写入文件
             lines++;
         }
         
@@ -99,7 +99,7 @@ int main()
         zt::print(
             "Caught an error because:\n",
             "\t",NAME_VALUE(e.what()),"\n"
-            "closing\n"
+            "Closing\n"
         );
     }catch(...){
         zt::print(