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  1. (defclass dice ()
  2.   ((prob-dist :initarg :prob-dist)
  3.    threshold))
  4.  
  5. (defmethod initialize-instance :after ((dice dice) &rest initargs)
  6.   (with-slots ((prob-dist prob-dist) (threshold threshold)) dice
  7.     (setf threshold
  8. 	  (nreverse (let ((sum (apply #'+ prob-dist)))
  9. 		      (reduce (lambda (a b) (cons (+ (car a) (/ b sum)) a))
  10. 			      prob-dist
  11. 			      :initial-value (list 0)))))))
  12.  
  13. (defmethod roll ((dice dice))
  14.   (position (random 1.0) (slot-value dice 'threshold)
  15. 	    :test #'<=))
  16.  
  17. (defun count-dice (prob-dist)
  18.   (loop with dice = (make-instance 'dice :prob-dist prob-dist)
  19. 	with count = (make-array (length prob-dist) :initial-element 0)
  20. 	repeat 1e5
  21. 	do (incf (elt count (1- (roll dice))))
  22. 	finally (loop for c across count
  23. 		      for i upfrom 1
  24. 		      do (format t "~a: ~a~%" i c))))
  25.  
  26. (count-dice '(1 2 1 2 1 2))
  27. (count-dice (loop for i from 1 to 4 collect (sqrt i)))
Success #stdin #stdout 4.83s 10824KB
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Standard input is empty
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1: 11192
2: 22195
3: 11241
4: 22080
5: 11048
6: 22244
1: 16247
2: 23070
3: 28206
4: 32477
https://ideone.com/NmtRP7
language:
Common Lisp (clisp 2.49.92)
created:
11 years ago
visibility:
public

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