1. A computer-implemented method for verifying membership of a code in one or more subsets of a global set, comprising: representing, using one or more processors, a subset C of the global set based on a Boolean clause assignment for the subset C =y 1 z 1 or y 2 z 2 or. .. or y i z i , wherein y i and z i represent a first word and a second word of respective Boolean clauses, a conjunction of which defines the subset C; determining that the code x i is a member of the subset C when: 
 (( x i XOR z i )AND y i )=0; verifying membership in one or more sets that are subsets of a the global set, wherein a co-occurrence count for each pair of codes in the subsets is determined, wherein a d-dimensional data structure is utilized to represent the global set, where one or more vertices of the d-dimensional data structure are respectively mapped to one or more members of the global set, using the co-occurrence count, and, wherein a one-bit word is added to a Boolean clause in one or more Boolean clauses used to define the subset C, wherein an indicator value indicates whether a corresponding Boolean clause uses the maximum of d Boolean literals; and wherein if the indicator value indicates that the corresponding Boolean clause uses the maximum of d Boolean literals, then the corresponding Boolean clauses includes the d-bit word with the values of said Boolean literals and excludes the first word and the second word, wherein when testing to determine if x i is a member of C as defined by the corresponding Boolean clause, x i is a member of C if ((x i XOR z i ) AND y i ) =0.