2. The computer-implemented method of claim 1 , further comprising: reducing a domain associated with the variable based on the sub-constraint and an assumption that the sub-constraint is held, whereby a reduced domain is determined; and wherein said selecting the variable comprises selecting a variable associated with the reduced domain.
2. The computer-implemented method of claim 1 , further comprising: reducing a domain associated with the variable based on the sub-constraint and an assumption that the sub-constraint is held, whereby a reduced domain is determined; and wherein said selecting the variable comprises selecting a variable associated with the reduced domain. 3. The computer-implemented method of claim 2 , wherein said limiting the corresponding domain comprises limiting the corresponding domain to the reduced domain.