13 lines
397 B
Common Lisp
13 lines
397 B
Common Lisp
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(defun binary-search (value array &optional (low 0) (high (1- (length array))))
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(if (< high low)
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nil
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(let ((middle (floor (+ low high) 2)))
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(cond ((> (aref array middle) value)
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(binary-search value array low (1- middle)))
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((< (aref array middle) value)
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(binary-search value array (1+ middle) high))
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(t middle)))))
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