  State-dependent cloning machines that have so far been considered either
deterministically copy a set of states approximately, or probablistically copy
them exactly. In considering the case of two equiprobable pure states, we
derive the maximum global fidelity of $N$ approximate clones given $M$ initial
exact copies, where $N>M$. We also consider strategies which interpolate
between approximate and exact cloning. A tight inequality is obtained which
expresses a trade-off between the global fidelity and success probability. This
inequality is found to tend, in the limit as $N{\to}{\infty}$, to a known
inequality which expresses the trade-off between error and inconclusive result
probabilities for state-discrimination measurements. Quantum-computational
networks are also constructed for the kinds of cloning machine we describe. For
this purpose, we introduce two gates: the distinguishability transfer and state
separation gates. Their key properties are described
