Cronerbly

Learnerbly Coding Exercise

The Spec

We have a set of tasks, each running at least daily, which are scheduled using some simple values in a text file. You might recognise this if you have written a crontab configuration in the past.

Examples of the the scheduler config:

• 30 1 /bin/run_me_daily
• 45 * /bin/run_me_hourly
• * * /bin/run_me_every_minute
• 19 /bin/run_me_sixty_times

The first field is the minute past the hour, the second field is the hour of the day and the third is the command to run. For both cases * means that it should run for all values of that field. In the above example, run_me_daily has been set to run at 1:30 am every day and run_me_hourly at 45 minutes past the hour every hour. The fields are whitespace-separated and each entry is on a separate line.

We want you to write a command-line program that takes a single argument. This argument is the simulated 'current time' in the format HH:MM. The program should accept config lines in the form above to STDIN and output the soonest time at which each of the commands will fire and whether it is today or tomorrow. In the case when the task should fire at the simulated 'current time' then that is the time you should output, not the next one.

For example given the above examples as input and the simulated 'current time' command-line argument 16:10 the output should be:

• 1:30 tomorrow - /bin/run_me_daily
• 16:45 today - /bin/run_me_hourly
• 16:10 today - /bin/run_me_every_minute
• 19:00 today - /bin/run_me_sixty_times

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