#include <windows.h>
#include <malloc.h>
 
#define TOTALBYTES    8192
#define BYTEINCREMENT 1024
 
DWORD BufferSize = TOTALBYTES;
PPERF_DATA_BLOCK PerfData = NULL;
 
while( RegQueryValueEx( HKEY_PERFORMANCE_DATA,
                        TEXT("Global"),
                        NULL,
                        NULL,
                        (LPBYTE) PerfData,
                        &BufferSize ) == ERROR_MORE_DATA )
{
// Get a buffer that is big enough.
 
    BufferSize += BYTEINCREMENT;
    PerfData = (PPERF_DATA_BLOCK) realloc( PerfData, BufferSize );
}

#include <windows.h>
#include <iostream>
using namespace std;
 
int main()
{
    HKEY hKey = 0;
    char buf[255] = {0};
    DWORD dwType = 0;
    DWORD dwBufSize = sizeof(buf);
    const char* subkey = "Software\\Microsoft\\Office\\PowerPoint\\AddIns\\MultiMgrAddIn.AddInDesigner1";
 
    if( RegOpenKey(HKEY_LOCAL_MACHINE,subkey,&hKey) == ERROR_SUCCESS)
    {
        dwType = REG_SZ;
        if( RegQueryValueEx(hKey,"Description",0, &dwType, (BYTE*)buf, &dwBufSize) == ERROR_SUCCESS)
        {
            cout << "key value is '" << buf << "'\n";
        }
        else
            cout << "can not query for key value\n";
        RegCloseKey(hKey);
 
    }
    else
        cout << "Can not open key\n";
    cin.ignore();
 
    return 0;
}

int main (void)
{
    using namespace std ;
 
    string key = "something     \ with   \ spaces           ." ;
    for ( int i = 0, j ; i < key.length( ) ; ++ i )
    {
        if ( key [i] == ' ' )
        {
            for ( j = i + 1; j < key.length ( ) ; ++j )
            {
                if ( key [j] != ' ' )
                    break ;
            }
 
            key = key.erase ( i, (j - i) ) ;
        }
    }
 
    cout << key ;
    getchar () ;
    return 0;
}