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To unify the discussion of file structures we need some further concepts
...1 the K pointers are distinct;2 each non null K pointer in L gives the address of a record within L;3 there is a unique record in L not pointed to by any record containing K;it is called the beginning of the list;and 4 there is a unique record in L containing the null K pointer;it is the end of the list
...Hsiao and Harary state condition 2 slightly differently so that no two K lists have a record in common;this only appears to complicate things
...From our previous example:K 1 list:R 1,R 2,R 5 K 2 list:R 2,R 4 K 4 list:R 1,R 2,R 3 Finally,we need the definition of a directory of a file
...Ki,ni,hi,ai 1,ai 2,...We are now in a position to give a unified treatment of sequential files,inverted files,index sequential files and multi list files
...Sequential files A sequential file is the most primitive of all file structures
...The implementation of this file structure requires the use of asorting routine
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