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(a)Using the given key value in each
case, calculate the address generated by the
following andomising techniques:
(i)Radix conversion to base 11 for key value 22.[2 marks ]
(ii)Extraction (based on first and third digit placing) for key value
1954.[1 mark ]
(iii)Assume 3000 records with key values 11000-13999 which are held
to a block
from block number 1500 upwards.Using self-addressing with key conversion,
find the location of key value 12784 with blocking factor 10.[2 marks
]
(iv)If there are 2000 blocks available, find the address location
fo key 27859 using
prime numbe division.[3 marks ]
Please do not
award half marks.
(i) (2 * 
) +( 2* 
) (1 mark)
=24
(1 mark) [2 marks ]
(ii) 15 [1 mark
]
(iii) (12784 - 11000
)/10 +1500 (1 mark)
=1678
(1 mark) [2 marks ]
(iv) 27859 / 1999(1
mark)
=13r1872
(1 mark)
=1872
(1 mark) [3 marks ]
(b)(i)Define the term synonym [1mark
]
A synonym occu r when two or more records are transformed to the same
location. Other valid answers should also receive credit. [1 mark
]
(ii)Describe three synonym handling techniques.[6 marks ]
One mark should be awarded for each technique named, and a further
mark should be awarded for each satisfactory elaboration (up to a
maximum of six marks). Examples include the following:
•Progressive over flow (1 mark).Synonyms are placed in the next
available
position after the home record (1 mark).
•Chained record (1 mark). The home record is linked to the first
synonym,
the fist synonym is linked to the second synonym, etc.(1 mark).
•Tagged record (1 mark). Each synonym in the over flow area is
pointed to
from the home area (1 mark). Other valid answers should also receive
credit. [6 marks ]
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