哪位高手懂C#的帮忙把这段用C++写一下

谁懂C#的帮忙把这段用C++写一下。
public static string hexchar2bin(string passWord)  
  {  
  StringBuilder builder = new StringBuilder();  
  for (int i = 0; i < passWord.Length; i = i + 2)  
  {  
  builder.Append(Convert.ToChar(Convert.ToInt32(passWord.Substring(i, 2), 16)));  
  }  
  return builder.ToString();  
  }  
谁懂C#的帮忙把这段用C++写一下。谢谢了。

[解决办法]

C/C++ code

#include <string>using namespace std;string hexchar2bin(string passWord)     {string str;       for (int i = 0; i < passWord.size(); i = i + 2)     { string str1 = passWord.substr(i,2);//hex2intint a;sscanf(str1.c_str(), "%x", &a);char s1[4];_itoa(a,s1,10);str += s1;      }     return str;     }