undeletion
 

how do i undelete files using inodes... i would like to write a program to implement this for my OS project... will it be feasible..

If it's delete from the User Interface, most modern UI's provide this service
by moving the deleted item to 'trash' where the user empties it periodically.

If it's delete from the command line, you can write an 'rm' alias which mv's the file to a trash directory.

Usually though, it's changing your work ethic to not delete files until you are sure you won't need it anymore. A trash can/trash directory is merely a crutch which provides a level of indirection to removing a file.
You have to ask yourself why you are removing a file.
Most items can be recreated, especially if you have a backup policy.

The likelyhood of finding all the blocks of a deleted file in the filesystem
is near zero.