Modify the program from the case study by maintaining an order during insertion of new records into the data file. This requires overloading the operator < in Personal and in Student to be used in a modified function add() in Database. The function finds a proper position for a record d, moves all the records in the file to make room for d, and writes d into the file. With the new organization of the data file, find() and modify() can also be modified. For example, find() stops the sequential search when it encounters a record greater than the record looked for (or reaches the end of file). A more efficient strategy can use binary search, discussed in Section 2.7.