Page "Wire wrap" Paragraph 49

The programs then try to reorder each net in the signal-pin list to " route " each signal in the shortest way.

The routing problem is equivalent to the travelling salesman problem, which is NP complete, and therefore not amenable to a perfect solution on a reasonable time scale.

One practical routing algorithm is to pick the pin farthest from the center of the board, then use a greedy algorithm to select the next-nearest pin with the same signal name.