21 lines
347 B
Common Lisp
21 lines
347 B
Common Lisp
(defun decrement (n) (- n 1))
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(defun percent (n percent)
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(if (> percent 0)
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(/ (+ (* n percent) 50) 100)
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(/ (- (* n percent) 50) 100)
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)
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)
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(defun compound-interest (principal rate years)
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(if (= years 0)
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principal
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(compound-interest
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(+ principal (percent principal rate))
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rate
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(decrement years)
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)
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)
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)
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