78c5704f34
Works fine either way - this is just since underscores are required in filenames for real projects, so it's something good for folks to get used to.
51 lines
1.1 KiB
Clojure
51 lines
1.1 KiB
Clojure
(defn is-even? [n]
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(if (= n 0)
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__
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(___ (is-even? (dec n)))))
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(defn is-even-bigint? [n]
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(loop [n n
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acc true]
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(if (= n 0)
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__
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(recur (dec n) (not acc)))))
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(defn recursive-reverse [coll]
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__)
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(defn factorial [n]
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__)
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(meditations
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"Recursion ends with a base case"
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(= true (is-even? 0))
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"And starts by moving toward that base case"
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(= false (is-even? 1))
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"Having too many stack frames requires explicit tail calls with recur"
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(= false (is-even-bigint? 100003N))
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"Reversing directions is easy when you have not gone far"
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(= '(1) (recursive-reverse [1]))
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"Yet more difficult the more steps you take"
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(= '(5 4 3 2 1) (recursive-reverse [1 2 3 4 5]))
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"Simple things may appear simple."
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(= 1 (factorial 1))
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"They may require other simple steps."
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(= 2 (factorial 2))
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"Sometimes a slightly bigger step is necessary"
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(= 6 (factorial 3))
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"And eventually you must think harder"
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(= 24 (factorial 4))
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"You can even deal with very large numbers"
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(< 1000000000000000000000000N (factorial 1000N))
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"But what happens when the machine limits you?"
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(< 1000000000000000000000000N (factorial 100003N)))
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