1. (use extras)
  2. (use srfi-69)
  4. (define maxc 100000)
  5. (define maxran 100000)
  7. (time
  8. (let loop ((count maxc) (n (random maxran)) (alist (list)))
  9. (if (> count 0)
  10. (loop (- count 1)
  11. (random maxran)
  12. (if (alist-ref n alist)
  13. (alist-update n (+ (alist-ref n alist) 1) alist)
  14. (alist-update n 1 alist))))))
  16. (time
  17. (let loop ((count maxc) (n (random maxran)) (alist (list)))
  18. (if (> count 0)
  19. (begin
  20. (if (alist-ref n alist)
  21. (alist-update! n (+ (alist-ref n alist) 1) alist)
  22. (alist-update! n 1 alist))
  24. (loop (- count 1) (random maxran) alist)))))
  26. (time
  27. (let loop ((count maxc) (n (random maxran)) (alist (make-hash-table)))
  28. (if (> count 0)
  29. (begin
  30. (if (hash-table-exists? alist n)
  31. (hash-table-set! alist n (+ (hash-table-ref alist n) 1))
  32. (hash-table-set! alist n 1))
  34. (loop (- count 1) (random maxran) alist)))))
  36. (time
  37. (let loop ((count maxc) (n (random maxran)) (alist (make-hash-table)))
  38. (if (> count 0)
  39. (begin
  40. (hash-table-set! alist n (+ (hash-table-ref/default alist n 0) 1))
  42. (loop (- count 1) (random maxran) alist)))))
  44. ;650.477s CPU time, 381.043s GC time (major), 232987/813312 GCs (major/minor)
  45. ;0.014s CPU time, 0/171 GCs (major/minor)
  46. ;0.112s CPU time, 0.009s GC time (major), 142497 mutations, 5/719 GCs (major/minor)
  47. ;0.107s CPU time, 0.011s GC time (major), 142534 mutations, 3/640 GCs (major/minor)