1. A computer-implemented method of determining if a query element is included in a set of elements comprising one or more elements from a first domain having a character set of “m” characters and “Z” is the maximum possible length of an element in the first domain, the method comprising: building a data structure based upon the set of elements, the data structure comprising “Z” memory structures, each memory structure comprising “m” slots, each slot comprising a first memory location and an array of memory locations, each array of memory locations comprising “(m+1)” memory locations; receiving information identifying the query element; and using the data structure to determine if the query element is included in the set of elements such that the number of comparisons needed to determine if the query element is included in the set of elements is proportional to a length of the query element and independent of the number of elements in the set of elements.