5. The method of claim 4, wherein selecting at least one variable of the selected constraint and selecting a new value for each selected variable comprise: altering, for one or more variables of the selected constraint, the current values of the variables to generate an altered current assignment; computing a score for the altered current assignment; ranking the scores for one or more altered current assignments; and selecting the variable and the new value for each selected variable according to the ranking.
5. The method of claim 4, wherein selecting at least one variable of the selected constraint and selecting a new value for each selected variable comprise: altering, for one or more variables of the selected constraint, the current values of the variables to generate an altered current assignment; computing a score for the altered current assignment; ranking the scores for one or more altered current assignments; and selecting the variable and the new value for each selected variable according to the ranking. 7. The method of claim 5, wherein the step of selecting a constraint from a set of unsatisfied constraints comprises distinguishing between one or more hard constraints and one or more soft constraints and selecting at least one hard constraint according to a parameter P.sub.HARD.