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- ;; Powerful digit sum
- (define-module (solved p056))
- (use-modules (srfi srfi-1)
- (euler utils))
- (define (find-max-digital-sum limit)
- (reduce max 0
- (map (lambda (n)
- (reduce + 0 (number->digits n)))
- (get-expt-nums limit))))
- (define (get-expt-nums limit)
- (let generator ([a 1] [b 1] [expt-nums '()])
- (cond
- [(>= a limit) expt-nums]
- [(>= b limit) (generator (1+ a) 1 expt-nums)]
- [else (generator a (1+ b) (cons (expt a b) expt-nums))])))
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