Long multiplication: Difference between revisions
→{{header|Common Lisp}}
m (→Iterative) |
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Line 1,800:
long-add do have the most significant bit first."
(if (every 'endp digitses)
(nconc (number->digits carry) sum)
(let ((column-sum (reduce '+ (mapcar #'first-digit digitses)
:initial-value carry)))
Line 1,810:
;; compute the zero padded rows. Then, add these rows (using
;; long-add) and convert the digits back to a number.
(do ((a (nreverse (number->digits a)))
(b (nreverse (number->digits b)))
(prefix '() (list* 0 prefix))
(rows '()))
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