13 lines
280 B
Scheme
13 lines
280 B
Scheme
;;; doubly recursive power (expt) function
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;;; try using trace-lambda to see the nesting.
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(define power
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(lambda (x n)
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(cond
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[(= n 0) 1]
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[(= n 1) x]
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[else
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(let ([q (quotient n 2)])
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(* (power x q) (power x (- n q))))])))
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