// return final size, include dataLengthMax
protected int RandomInMin(int dataLengthMin, int dataLengthMax)
{
dataLengthMin -= tree_offset;
dataLengthMax -= tree_offset;
int len = tree.RandomFindIndex(dataLengthMin - 1, dataLengthMax, random);
tree.Update(len);
return(len + tree_offset + 1);
}
