code: private static boolean isIllPosed(double minMass, double maxMass, MolecularFormulaRange mfRange) {
          // when the number of integers to decompose is incredible large
          // we have to adjust the internal settings (e.g. precision!)
          // instead we simply fallback to the full enumeration method
          if (maxMass - minMass >= 1) return true;
          if (maxMass > 400000) return true;
          // if the number of elements to decompose is very small
          // we fall back to the full enumeration methods as the
          // minimal decomposable mass of a certain residue class might
          // exceed the 32 bit integer space
          if (mfRange.getIsotopeCount() <= 2) return true;
  
          // if the mass of the smallest element in alphabet is large
          // it is more efficient to use the full enumeration method
          double smallestMass = Double.POSITIVE_INFINITY;
          for (IIsotope i : mfRange.isotopes()) {
              smallestMass = Math.min(smallestMass, i.getExactMass());
          }
  
          return smallestMass > 5;
      }
docs: Decides wheter to use the round robin algorithm or full enumeration algorithm.
  The round robin implementation here is optimized for chemical elements in organic compounds. It gets slow
  if
  - the mass of the smallest element is very large (i.e. hydrogen is not allowed)
  - the maximal mass to decompose is too large (round robin always decomposes integers. Therefore, the mass have
  to be small enough to be represented as 32 bit integer)
  - the number of elements in the set is extremely small (in this case, however, the problem becomes trivial anyways)
  
  In theory we could handle these problems by optimizing the way DECOMP discretizes the masses. However, it's easier
  to just fall back to the full enumeration method if a problem occurs (especially, because most of the problems
  lead to trivial cases that are fast to compute).
  
  @return true if the problem is ill-posed (i.e. should be calculated by full enumeration method)