passing string type to C++

[Saeed]

'Get' : cannot convert parameter 1 from 'char *' to 'struct tagSAFEARRAY *'

#include "stdafx.h"
#include "tchar.h"
#include <comutil.h>

#include <string>
// Import the type library.

//#import "..\ManagedDLL\bin\Debug\ManagedDLL.tlb" raw_interfaces_only
#import "C:\Mydot-net-projects\sManagedDLL\sManagedDLL\bin\Debug\sManagedDLL.tlb"
using namespace sManagedDLL;
int _tmain(int argc, _TCHAR* argv[])
{
    // Initialize COM.
    HRESULT hr = CoInitialize(NULL);

    // Create the interface pointer.
    ICalculatorPtr pICalc(__uuidof(ManagedClass));

    long lResult = 0;
	std::string str;

    // Call the Add method.
//    pICalc->Add(5, 10, &lResult);
    wprintf(L"The result1 is [%d]\n", pICalc->Add(5, 10));
	char p[10];


	char *szTemp = new char [1000];
	strcpy(szTemp,"Test");
    wprintf(L"The result2 is p=[%s]\n",pICalc->Get(szTemp) );


    // Uninitialize COM.
    CoUninitialize();
    return 0;
}

and in C#

using System;
using System.Collections.Generic;
using System.Text;

namespace sManagedDLL
{

    // Interface declaration.
    public interface ICalculator
    {
        int Add(int Number1, int Number2);
        string Get(char [] s);
    };
    // Interface implementation.
    public class ManagedClass : ICalculator
    {
        public int Add(int Number1, int Number2)
        {
            return Number1 + Number2+3;
        }
        public string Get(char[] s)
        {
            StringBuilder sBuffer = new StringBuilder(100);
            return sBuffer.ToString();
          
        }
    }
}