backups for tower of hanoi progression
hello all
Can anyone plz tell me a way for implementing the backup plan for tower of hanoi progression.I am not pretty sure with my answer.
Any help will be appreciated.
Regards
venkat
The following backup scheme is based on the Tower of Hanoi progression:
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Sun Mon Tues Wed Thu Fri Sat
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0 3 2 5 4 7 6
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a)For each day list the backups that would be required to completely restore the machine on that day.
b)If a file was changed on Monday which backups would have a copy of that file? Repeat for the other days of the week.
solution:
a)It starts with a level 0 (full) on Monday. Suppose that a file is changed on Tuesday. The level 3 on Tuesday would back up everything since the level 0, so that changed file would be included on Tuesday's backup. Suppose that on Wednesday we change another file. Then on Wednesday night, the level 2 backup must look for a level that is lower, right? The level 3 on Tuesday is not lower, so it will reference the level 0 also. So the file that was changed on Tuesday, as well as the file that was changed on Wednesday, gets backed up again. On Thursday, the level 5 will back up just what changed that day, since it will reference the level 2 on Wednesday.
But on Friday, the level 4 will not reference the level 5 on Thursday; it will reference the level 2 on Wednesday.
what would be the solution for part (b) question?
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