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#include <windows.h>
#define WINDCLASSNAME	L"HELLOWORLD2"
int g_nExit = 0;

LRESULT WINAPI MsgProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam ){
	switch( msg ){
	case WM_DESTROY:
	case WM_CLOSE:
		g_nExit = 1;
		return 0;
	}
	return DefWindowProc( hWnd, msg, wParam, lParam );
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR lpCmdLine, int nCmdShow ){
	WNDCLASSEX hWndClass = {sizeof(WNDCLASSEX), CS_CLASSDC ,MsgProc, 0L, 0L, GetModuleHandle(NULL), NULL, NULL, NULL, NULL, WINDCLASSNAME, NULL};
	RegisterClassEx( &hWndClass );
	int w = 400 + GetSystemMetrics(SM_CXEDGE) + GetSystemMetrics(SM_CXBORDER) + GetSystemMetrics(SM_CXDLGFRAME);
	int h = 300 + GetSystemMetrics(SM_CYEDGE) + GetSystemMetrics(SM_CYBORDER) + GetSystemMetrics(SM_CYDLGFRAME) + GetSystemMetrics(SM_CYCAPTION);
	HWND hWnd = CreateWindow( WINDCLASSNAME, L"こんにちわ、GUI！", WS_OVERLAPPEDWINDOW, 100, 100, w, h, GetDesktopWindow(), NULL, hWndClass.hInstance, NULL );
	ShowWindow(hWnd, SW_SHOWDEFAULT);
	UpdateWindow(hWnd);
	MSG msg;
	while(g_nExit==0){
		if( PeekMessage( &msg, NULL, 0U, 0U, PM_REMOVE ) ){
			TranslateMessage( &msg );
			DispatchMessage( &msg);
		}
	}
	UnregisterClass( WINDCLASSNAME, hWndClass.hInstance );
	return 0;
}