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| • |
Charge
7 credits for each
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operation
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– |
Amortized
time per
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operation
is O(1)
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| • |
addElement()
(when no
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doubling
occurs) uses one
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credit
to pay for itself and
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stores
6 credits with the item
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| • |
The
other operations use
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their
7 credits to pay for
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themselves
with the extra 6
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credits
thrown away
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| • |
When
a table doubling
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occurs
(say at size 2i)
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– |
It takes 3*2i credits to pay
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for
creating the new array
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and
copying all the data
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– |
We use
the credits stored at
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positions
2i-1 to 2i
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| • |
Note
that the previous
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doubling
occurred when the
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size
was 2i-1
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– |
Thus
the credits stored at
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2i-1
to 2i are unspent
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