METHOD AND APPARATUS FOR DYNAMICALLY VARYING NET RULES

Permutations of orders of elements such as electrical connection pins, vias and t-junctions at known locations are efficiently tested against at least type and distance criteria by forming a plurality of lists of the elements and screening the elements of each list against respective ones of said type criteria to reduce the length of the lists of elements. Pointers to ones of the distance criteria and remaining members of a list corresponding to respective ones of the distance criteria iteratively form pairs of elements which are checked for separation. When the check fails or a solution is found, the pointer to list members is advanced. The pointer to respective distance criteria is advanced when a check is successful. When a list is exhausted and a check is unsuccessful, the pointer to respective distance criteria is regressed. Advancement and regression of pointers reduces iterations of combinations of pairs of elements which do not lead to a solution in order to accelerate the process. Each new solution is evaluated against a single stored prior solution for optimization of solutions while greatly reducing storage requirements.