public @Nullable RelationType getRelation(int c1Index, int c2Index) {
    if (areDistinctUnordered(c1Index, c2Index)) {
      return RelationType.NE;
    }
    if (myData.contains(createPair(c1Index, c2Index, true))) {
      return RelationType.LT;
    }
    if (myData.contains(createPair(c2Index, c1Index, true))) {
      return RelationType.GT;
    }
    return null;
  }
public @Nullable RelationType getRelation(int c1Index, int c2Index)