private int?MoveDownLeft(int currentNo, List <int> sequence)
{
int?nextNo = Keypad.DownOf(currentNo);
if (nextNo.HasValue)
{
nextNo = Keypad.DownOf(nextNo.Value);
if (nextNo.HasValue)
{
nextNo = Keypad.LeftOf(nextNo.Value);
if (nextNo.HasValue && !sequence.Contains(nextNo.Value))
{
return(nextNo);
}
}
}
return(null);
}
private int?MoveUpRight(int currentNo, List <int> sequence)
{
int?nextNo = Keypad.UpOf(currentNo);
if (nextNo.HasValue)
{
nextNo = Keypad.UpOf(nextNo.Value);
if (nextNo.HasValue)
{
nextNo = Keypad.RightOf(nextNo.Value);
if (nextNo.HasValue && !sequence.Contains(nextNo.Value))
{
return(nextNo);
}
}
}
return(null);
}
