18 lines
581 B
Text
18 lines
581 B
Text
When we are running the iter line:
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(iter (cdr things)
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(cons (square (car things))
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answer))))
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We are essentially pushing on the "answer" accumulator list
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like a stack, so when we start with items = (1 2 3), answer =
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().
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When we run the loop once we get:
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things = (2 3), answer = (1)
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things = (3), answer = (4 1)
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things = (), answer = (9 4 1).
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When Louis changes the order in the cons, he just produces the
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following:
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things = (1 2 3), answer = ()
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things = (2 3), answer = (() . 1)
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things = (3), answer = ((() . 1) . 4)
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things = (), answer = (((() . 1) . 4) . 9)
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