scheme recursion - power of an int -

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i trying implement function tells if parameter power of 2. here have

   (define (powof2 x) (cond      [(and (even? x) (> x 1)) ((powof2 (/ x 2)))]     [else (equal?(x 1))]))

but when try run parameter 12 error saying: error: 3 not function [powof2, powof2, powof2, (anon)]

any help?

thanks!

ah parenthesis ;-)

(define (powof2 x)   (cond       [(and (even? x) (> x 1)) (powof2 (/ x 2))]     [else (= x 1)]))

note in 3rd line , 4th line had pair of parenthesis, , in 4th line should use = compare numbers.


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