20 lines
404 B
Common Lisp
20 lines
404 B
Common Lisp
(defun decrement (n) (- n 1))
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(defun percent (n percent)
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(cond
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((> percent 0) (/ (+ (* n percent) 50) 100))
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(t (/ (- (* 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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(cond
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((= years 0) principal)
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(t (compound-interest (+ 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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)
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