ReadProcessMemory CheatEngine Value

Question

I want to get a value from a Proccess, here it's a simple test with "Calculator". First, I get the address with CheatEngine. Secondly I put it in ReadProcessMemory. But ReadProcessMemory return 0, I think I miss something, I've found something with BaseAddress, but I still have bad results. Google is out of results for me, so I ask you!

#include <windows.h>
#include <iostream>
#include <conio.h>

using namespace std;

int main()
{
    int value;
    DWORD pid;
    HWND hwnd = FindWindow(NULL,"Calculatrice");
    if(!hwnd)
    {
             cout << "Window not found!";
    }
    else
    {
        GetWindowThreadProcessId(hwnd,&pid);
        HANDLE phandle = OpenProcess(PROCESS_ALL_ACCESS,0,pid);
        if(!phandle)
        {
                cout <<"Could not get handle!";
        }
        else
        {
                cout << ReadProcessMemory(phandle,(LPVOID)0xC71657E900,&value,sizeof(value),0) << endl;
                cout << value;
                getch();
                return 0;
        }
    }
}

Answer 1

Resolved ! When the address is too big, because it's a 64bit address, the program change to a 32bit address, that's why it don't work.

So, in Visual Studio, set to x64.