请大神帮我看看我的这段程序错在哪里，运行不出来呀。告急！！！！

#include 

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
							PSTR szCmdLine, int iCmdShow)
{
	const wchar_t CLASS_NAME[] = L"Sample Window Class";

	WNDCLASS wc = {};

	wc.lpfnWndProc = WindowProc;
	wc.hInstance = hInstance;
	wc.lpszClassName = CLASS_NAME;

	RegisterClass(&wc);

	HWND hwnd = CreateWindowEx(0, CLASS_NAME, L"Learn to Program Windows", WS_OVERLAPPEDWINDOW | WS_VISIBLE, 500, 500,
		500, 500, NULL, NULL, hPrevInstance, NULL);
	if (hwnd == NULL)
	{
		return 0;
	}

	ShowWindow(hwnd, iCmdShow);

	MSG msg = {};

	while (GetMessage(&msg, NULL, 0, 0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	return 0;
}

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	switch (uMsg)
	{
	case WM_DESTROY:
		PostQuitMessage(0);
		return 0;

	case WM_PAINT:
	{
					 PAINTSTRUCT ps;
					 HDC hdc = BeginPaint(hwnd, &ps);

					 FillRect(hdc, &ps.rcPaint, (HBRUSH)(COLOR_WINDOW + 1));

						 EndPaint(hwnd, &ps);
	}
		return 0;

	}
	return DefWindowProc(hwnd, uMsg, wParam, lParam);
}