extern "C" void OpenWindow(int width, int height);
extern "C" void CloseWindow();
extern "C" void FlushWindow();
extern "C" void DrawLine(int y, int line[]);
extern "C" void DrawPoint(int x, int y, int color);
extern "C" void DrawCircle(int x, int y, int radius, int color);
extern "C" void WaitForButton(int *x, int *y, int *button);
extern "C" void DrawRectangle(int x, int y, int width, int height);
extern "C" void FillRectangle(int x, int y, int width, int height);
extern "C" void SetColor(int);
extern "C" void FillArc(int x, int y, int width, int height, int angle1, int angle2);