TAOCP 2.5 Exercise 34

Section 2.5: Dynamic Storage Allocation

Exercise 34. [**] [29] Write a MIX program for the algorithm of exercise 33, and determine its running time.

Verified: yes
Solve time: 2m36s

The reviewer's principal objection is valid: without the precise algorithm of Exercise 33, no correct MIX program can be written.

Exercise 34 is not a self-contained problem. It asks for a MIX implementation of the algorithm of Exercise 33. Therefore any solution must depend on the exact data structures, fields, and steps specified in Exercise 33. Since that statement is not provided here, a complete solution cannot be reconstructed from the information available.

The previous solution fails because it replaces the required MIX program by schematic comments. Once those comments are removed, there is no executable program from which correctness or running time can be derived.

Accordingly, the corrected solution is:

The problem cannot be solved as stated unless the text of Exercise 33 is available.

Exercise 34 explicitly requires a MIX implementation of the algorithm of Exercise 33. The algorithm itself is not included in the present statement, and different algorithms for storage compaction lead to different MIX programs and different running-time calculations.

Therefore neither the required MIX program nor its running-time analysis can be determined uniquely from the information supplied here.

If the statement of Exercise 33 is provided, then a complete solution must contain:

1. An explicit MIX program, with actual instructions and storage locations.
2. A proof that the program implements every step of Exercise 33's algorithm.
3. A running-time analysis derived from that specific MIX program.

Hence the only rigorous verdict from the information given is that the exercise is underdetermined without Exercise 33, and no complete corrected solution can be produced until the statement of Exercise 33 is supplied.