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#  The submit system, courtesy of Prof. Eisenstat
#  1/16/14
# Please name your Racket solution files: hw0.rkt, hw1.rkt, hw2.rkt, ...
# 
#  submit    assignment-number file(s)
#  unsubmit  assignment-number file(s)
#  check     assignment-number
#  protect   assignment-number file(s)
#  unprotect assignment-number file(s)
#  retrieve  assignment-number file(s)
#
#  The submit program can be invoked in six different ways:
#
#      /home/classes/cs201/bin/submit  0  hw0.rkt
#
#  submits the named source file as your solution to homework #0;
#  for homework #1, please change 0 to 1 and hw0.rkt to hw1.rkt, etc;
#
#      /home/classes/cs201/bin/check  1
#
#  lists the files that you have submitted for homework #1;
#
#      /home/classes/cs201/bin/unsubmit  2  oops.rkt
#
#  deletes the named file that you had submitted previously for homework #2
#  (i.e., withdraws it from submission, which is useful if you accidentally
#  submit the wrong file);
#
#      /home/classes/cs201/bin/protect  3  hw3.rkt
#
#  protects the named file that you submitted previously for homework #3 (so
#  it cannot be deleted accidentally); and
#
#      /home/classes/cs201/bin/unprotect  4  hw4.rkt
#
#  unprotects the named file that you submitted previously for homework #4
#  (so it can be deleted); and
#
#      /home/classes/cs201/bin/retrieve  5  hw5.rkt
#
#  retrieves a copy of the named file that you submitted previously for
#  homework #5 (in case you accidentally delete your own copy).
#
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