public List<Entry<Integer, FastSparseSet<Integer>>> entryList() {
    List<Entry<Integer, FastSparseSet<Integer>>> list = new ArrayList<>();

    for (int i = 2; i >= 0; i--) {
      int ikey = 0;
      for (final FastSparseSet<Integer> ent : elements[i]) {
        if (ent != null) {
          final int key = i == 0 ? ikey : (i == 1 ? ikey + VarExprent.STACK_BASE : -ikey);

          list.add(new Entry<>() {

            private final Integer var = key;
            private final FastSparseSet<Integer> val = ent;

            @Override
            public Integer getKey() {
              return var;
            }

            @Override
            public FastSparseSet<Integer> getValue() {
              return val;
            }

            @Override
            public FastSparseSet<Integer> setValue(FastSparseSet<Integer> newvalue) {
              return null;
            }
          });
        }

        ikey++;
      }
    }

    return list;
  }
public List<Entry<Integer, FastSparseSet<Integer>>> entryList()