#include<iostream>
#include<string>
using namespace std;
int main()
{
//string filePath = "D:\\statistics_chengqichao\\qcc\\biaoxiandianyun.xyz";
//int nPos = filePath.rfind('\\');
//string prefixPath = filePath.substr(0, filePath.length() - nPos-1);
//cout << prefixPath << endl;
string filename = "C:\\MyDirectory\\MyFile.txt";
string directory;
const size_t last_slash_idx = filename.rfind('\\');
if (std::string::npos != last_slash_idx)
{
directory = filename.substr(0, last_slash_idx);
}
cout << directory << endl;
system("pause");
return 0;
}