1. A computer-readable medium having stored thereon a data structure for matching input values, the data structure comprising: a first element of a subtree, the subtree including a root node; and a second element of the subtree; wherein the first and the second elements each include: a node value field for indicating one or more paths from the root node through the subtree for reaching the respective first or second element; and wherein the first element includes: a next node indication for use in traversing to the second element.