message: Get rid of if statement in previous commit
  Instead use pointer arithmetic to circumvent array bounds checking
diff: @@ -99,9 +99,7 @@ void CoarseFineTransformations::GetCoarseToFineMap(
  cf_i[0] = 0;
  for (int i = 0; i < coarse_ne; i++)
  {
  - Pair<int,int> *end =
  - (cf_i[i+1] == cf_j.Size()) ? cf_j.end() : &cf_j[cf_i[i+1]];
  - std::sort(&cf_j[cf_i[i]], end);
  + std::sort(&cf_j[cf_i[i]], cf_j.GetData() + cf_i[i+1]);
  }
  for (int i = 0; i < fine_ne; i++)
  {
  