your program takes names of two files - infile and outfile - as
commmand-line parameters.  infile contains a list of commands to
execute and details related to each command.  This information is
provided in the form of (serial number, userid, est-time, command)
quadruples, so that each line of infile contains a three digit serial
number (beginning with 000), a three digit user id, an estimated
amount of cpu time (in milliseconds) required for completing the
request, and finally the command to be executed with its options,
where the fields are separated by single spaces. Your program reads
the entire file, puts the commands (with relevant details) in a queue,
ordering the requests according to the shortest job first scheme.  The
shortest job first scheme carries out commands with lower estimated
cpu time requirements before commands with higher estimated cpu time
requirements.

As myscheduler executes commands, it reorders remaining requests in
the queue based on the discrepancy in the estimated amount of cpu time
required by the commands which have already been executed.
Specifically, after executing a command, if the program sees that the
actual amount of cpu time taken is larger than the estimated time, it
increases estimated time for each remaining command request by the
same user by the same percentage, and then re-orders the queue;
however, if the actual time is less than the given estimate, it does
not change anything.

Your program continues until all commands have been executed, and
finally, writes to outfile the order in which the commands were
executed (by writing serial numbers of requests in the order in which
they were executed - one serial number per line), followed by the
average amount of discrepancy in estimates for commands requested by
each user (by writing a userid, followed by average amount of
discrepancy (in milliseconds) with respect to the estimates provided
in infile, followed by discrepancy with respect to the modified
estimates at the time of the execution of the commands) - one user's
information per line).  Fields on the same line in the discrepancy
part of outfile should be separated by single spaces.
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