// Return the operator's category that is the lowest among the applicable
// operators for state.
public static int LowestOperatorCategory(GoBangBoard board)
{
// A maximum, not important, just must be larger than any real
// category
int max = 99;
// Search category 0 and 1 in G_5
foreach (GoBangBoard.StoneSet ss in board.G5)
{
// There is no category below zero, so we can return early.
if (GBOperatorFive.Present(ss))
{
return(0);
}
if (GBOperatorFour.Present(ss))
{
max = 1;
}
}
if (max < 99)
{
return(max);
}
// Search category 1 and 2 in G_6
foreach (GoBangBoard.StoneSet ss in board.G6)
{
// If there was no 0/1 before, this is certainly the minimum.
if (GBOperatorStraightFour.Present(ss))
{
return(1);
}
if (max > 2 && GBOperatorBrokenThree.Present(ss))
{
max = 2;
}
else if (max > 2 && GBOperatorThree3.Present(ss))
{
max = 2;
}
}
if (max < 99)
{
return(max);
}
foreach (GoBangBoard.StoneSet ss in board.G7)
{
if (GBOperatorThree2.Present(ss))
{
return(2);
}
}
return(99);
}