Accumulate Adding and Counting
From Progzoo
Adding and Counting
It mayu help is you look at these examples before you start. Using an Accumulator
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Using an accumulator to add.
The variable list is an array, it holds several integers. For example it might be the list {1,2,3,4}.
You can iterate over a list, every time you visit an element of the list you do something to the accumulator acc
In this example, for every member v of the list you add that member to the accumulator using the code
acc = acc + v;
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Using an accumulator to count.
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Using an accumulator to multiply.
Use the accumulator to find the product of items in the list:
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Using an accumulator to max.
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Count Twos.
Use the accumulator to find the number of twos in the list: Count on a condition
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Count Non-Twos.
Use the accumulator to find number other than 2:
f({1,1,1,1}) -> 4
f({2,2,2}) -> 0
f({1,1,1,1,1}) -> 5
f({4,2,6,0,0}) -> 4
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Count the big numbers
Use the accumulator to count all numbers larger than 1:
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Add the big numbers
Use the accumulator to sum all numbers larger than 1:
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