docs: public boolean eq(IntIntSortedVector other) {
          // This is slow, but correct.
          IntIntSortedVector v1 = IntIntSortedVector.getWithNoZeroValues(this);
          IntIntSortedVector v2 = IntIntSortedVector.getWithNoZeroValues(other);
                  
          if (v2.size() != v1.size()) {
              return false;
          }
  
          for (IntIntEntry ve : v1) {
              if (!Primitives.equals(ve.get(), v2.get(ve.index()))) {
                  return false;
              }
          }
          for (IntIntEntry ve : v2) {
              if (!Primitives.equals(ve.get(), v1.get(ve.index()))) {
                  return false;
              }
          }
          return true;
      }