2. The method of claim 1 wherein translating the components of the set of sellable units that do not include a crossed combination of priceable units further comprises: adding a context free grammar rule for each of the sellable units.
2. The method of claim 1 wherein translating the components of the set of sellable units that do not include a crossed combination of priceable units further comprises: adding a context free grammar rule for each of the sellable units. 4. The method of claim 2 wherein the sellable units are priceable units, the method further comprising using faring-atoms to represent sets of flights, and adding a context-free grammar rule further comprises: adding a rule for each faring-atom FA[k] of length L[k] as: FA[k]==>Flight[k][1] . . . Flight[k][L[k]], wherein the symbol “==>” denotes producing.