windows下如何获取系统已存在的盘符 【c++】

#include <iostream>
#include "classAh.h"
#include <atlstr.h> 
using namespace std;


int main()
{
    char rootPath[10] = {0}, driveType[21] = {0};  
    UINT nType;  

    for(char a = 'A'; a <= 'Z'; a++)  
    {  
        sprintf(rootPath, "%c:\", a);  
        nType = GetDriveType(rootPath);  
        if(nType != DRIVE_NO_ROOT_DIR)                  // DRIVE_NO_ROOT_DIR: 路径无效  
        {  
            switch(nType)  
            {  
            case DRIVE_FIXED:  
                strcpy(driveType, "硬盘");  
                break;  
            case DRIVE_REMOVABLE:  
                strcpy(driveType, "移动硬盘");  
                break;  
            case DRIVE_CDROM:  
                strcpy(driveType, "光盘");  
                break;  
            case DRIVE_RAMDISK:  
                strcpy(driveType, "RAM盘");  
                break;  
            case DRIVE_REMOTE:  
                strcpy(driveType, "Remote(Network) drive 网络磁盘");  
                break;  
            case DRIVE_UNKNOWN:  
            default:  
                strcpy(driveType, "未知盘");  
                break;  
            }  
            cout<<rootPath<<"	"<<driveType<<endl;  
        }  
    }  
    
    getchar();
    return 0;
}