  In this paper, we exhibit two unital, separable, nuclear ${\rm C}^*$-algebras
of stable rank one and real rank zero with the same ordered scaled total
K-theory, but they are not isomorphic with each other, which forms a
counterexample to Elliott Classification Conjecture for real rank zero setting.
Thus, we introduce an additional normal condition and give a classification
result in terms of total K-theory. For the general setting, with a new
invariant -- total Cuntz semigroup \cite{AL}, we classify a large class of
${\rm C}^*$-algebras obtained from extensions. The total Cuntz semigroup, which
distinguish the algebras of our counterexample, could possibly classify all the
${\rm C}^*$-algebras of stable rank one and real rank zero.
