a2test.drs, available from the class web site. You should not need to make changes to this file. Your program should not load this file; instead you should load it by hand when in interactive mode.It should be clear from the test cases what the number and meaning of the parameters are of the functions called there. Note that in Scheme you needn't have a special type for fillers, or reclaim storage.
If lookup fails, you should return the value #f.