Computer with two-dimensional merge tournament sort using offset-value coding

Claim 1

A computer system, comprising: storage means for storing a list of records R 1 , . . . , R N to be sorted where each record is associated with a corresponding one of the keys K 1 , . . . , K N , respectively, for ordering the records, processing means for processing said records and keys and for controlling said storage means, said processing means including, means for forming a two-dimensional tree having a tree structure in said storage means where said tree structure is formed of nodes including a single root node and a plurality of leaf nodes where each node except the root node is a child of exactly one parent node and wherein, said nodes form a logical tree having a binary tree structure where each node is a parent node of at most two child nodes, said two-dimensional tree is organized into a tree structure of a plurality of subtrees, where each subtree is formed by a plurality of said nodes organized in a binary tree structure, and where for each particular node in a particular subtree that is the root node in the particular subtree, then said particular node has a parent node that is a leaf node in another subtree whereby said another subtree is the parent subtree of the particular subtree, code means for storing codes representing keys into said nodes, sort means for performing a tree sort of said keys using said codes by accessing subtrees.