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Each
operation (push, pop,
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clear)
is charged some
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number
of credits
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The
credits are used to pay
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for
computer time
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It
costs one credit to do a
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constant
time operation
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Total
time is proportional to
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total
number of credits
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Amortized
time for an
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operation
is determined by
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the
credits charged for that
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operation
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Analysis
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Each
operation is charged 2
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credits
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O(1)
amortized time per op
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For
push()
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Costs
one credit to do the
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push()
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The
other credit is stored
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with
the item on the Stack
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For
clear()
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The
credits in the Stack are
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used
to pay for clearing the
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Stack
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