Modify the algorithm in Figure 9.15 to handle the case in which both input files contain a record with the same key field value. Assume that these records are identical and that only one should appear...

Modify the algorithm in Figure 9.15 to handle the case in which both input files contain a record with the same key field value. Assume that these records are identical and that only one should appear in the output file. Design a system by which a file stored on a disk can be processed as a sequential file with either of two different orderings.