/// <summary>
/// Precalculate a union/intersection.
/// </summary>
/// <param name="unionTemp">
/// Set to recieve the union/intersection result.
/// </param>
/// <param name="i">
/// Size of first set.
/// </param>
/// <param name="j">
/// Index of first set.
/// </param>
/// <param name="k">
/// Size of second set.
/// </param>
/// <param name="l">
/// Index of second set.
/// </param>
private void PrecalcAUnionIntersect(Set unionTemp, int i, int j, int k, int l)
{
unionTemp.TakeRealUnion(elements[i][j], elements[k][l]);
int index = elements[unionTemp.Size].BinarySearch(unionTemp);
unionsSize[elements[i][j].num, elements[k][l].num] = elements[unionTemp.Size][index].Size;
unionsIndex[elements[i][j].num, elements[k][l].num] = index;
unionTemp.TakeRealIntersection(elements[i][j], elements[k][l]);
index = elements[unionTemp.Size].BinarySearch(unionTemp);
intersectionsSize[elements[i][j].num, elements[k][l].num] = elements[unionTemp.Size][index].Size;
intersectionsIndex[elements[i][j].num, elements[k][l].num] = index;
}
