gl_anyhash_primes.h 4.7 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687
  1. /* Table of primes, for use by hash tables.
  2. Copyright (C) 2006, 2009-2020 Free Software Foundation, Inc.
  3. Written by Bruno Haible <bruno@clisp.org>, 2006.
  4. This program is free software: you can redistribute it and/or modify
  5. it under the terms of the GNU General Public License as published by
  6. the Free Software Foundation; either version 3 of the License, or
  7. (at your option) any later version.
  8. This program is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11. GNU General Public License for more details.
  12. You should have received a copy of the GNU General Public License
  13. along with this program. If not, see <https://www.gnu.org/licenses/>. */
  14. /* Array of primes, approximately in steps of factor 1.2.
  15. This table was computed by executing the Common Lisp expression
  16. (dotimes (i 244) (format t "nextprime(~D)~%" (ceiling (expt 1.2d0 i))))
  17. and feeding the result to PARI/gp. */
  18. static const size_t primes[] =
  19. {
  20. 11, 13, 17, 19, 23, 29, 37, 41, 47, 59, 67, 83, 97, 127, 139, 167, 199,
  21. 239, 293, 347, 419, 499, 593, 709, 853, 1021, 1229, 1471, 1777, 2129, 2543,
  22. 3049, 3659, 4391, 5273, 6323, 7589, 9103, 10937, 13109, 15727, 18899,
  23. 22651, 27179, 32609, 39133, 46957, 56359, 67619, 81157, 97369, 116849,
  24. 140221, 168253, 201907, 242309, 290761, 348889, 418667, 502409, 602887,
  25. 723467, 868151, 1041779, 1250141, 1500181, 1800191, 2160233, 2592277,
  26. 3110741, 3732887, 4479463, 5375371, 6450413, 7740517, 9288589, 11146307,
  27. 13375573, 16050689, 19260817, 23112977, 27735583, 33282701, 39939233,
  28. 47927081, 57512503, 69014987, 82818011, 99381577, 119257891, 143109469,
  29. 171731387, 206077643, 247293161, 296751781, 356102141, 427322587,
  30. 512787097, 615344489, 738413383, 886096061, 1063315271, 1275978331,
  31. 1531174013, 1837408799, 2204890543UL, 2645868653UL, 3175042391UL,
  32. 3810050851UL,
  33. #if SIZE_MAX > 4294967295UL
  34. 4572061027UL, 5486473229UL, 6583767889UL, 7900521449UL, 9480625733UL,
  35. 11376750877UL, 13652101063UL, 16382521261UL, 19659025513UL, 23590830631UL,
  36. 28308996763UL, 33970796089UL, 40764955463UL, 48917946377UL, 58701535657UL,
  37. 70441842749UL, 84530211301UL, 101436253561UL, 121723504277UL,
  38. 146068205131UL, 175281846149UL, 210338215379UL, 252405858521UL,
  39. 302887030151UL, 363464436191UL, 436157323417UL, 523388788231UL,
  40. 628066545713UL, 753679854847UL, 904415825857UL, 1085298991109UL,
  41. 1302358789181UL, 1562830547009UL, 1875396656429UL, 2250475987709UL,
  42. 2700571185239UL, 3240685422287UL, 3888822506759UL, 4666587008147UL,
  43. 5599904409713UL, 6719885291641UL, 8063862349969UL, 9676634819959UL,
  44. 11611961783951UL, 13934354140769UL, 16721224968907UL, 20065469962669UL,
  45. 24078563955191UL, 28894276746229UL, 34673132095507UL, 41607758514593UL,
  46. 49929310217531UL, 59915172260971UL, 71898206713183UL, 86277848055823UL,
  47. 103533417666967UL, 124240101200359UL, 149088121440451UL, 178905745728529UL,
  48. 214686894874223UL, 257624273849081UL, 309149128618903UL, 370978954342639UL,
  49. 445174745211143UL, 534209694253381UL, 641051633104063UL, 769261959724877UL,
  50. 923114351670013UL, 1107737222003791UL, 1329284666404567UL,
  51. 1595141599685509UL, 1914169919622551UL, 2297003903547091UL,
  52. 2756404684256459UL, 3307685621107757UL, 3969222745329323UL,
  53. 4763067294395177UL, 5715680753274209UL, 6858816903929113UL,
  54. 8230580284714831UL, 9876696341657791UL, 11852035609989371UL,
  55. 14222442731987227UL, 17066931278384657UL, 20480317534061597UL,
  56. 24576381040873903UL, 29491657249048679UL, 35389988698858471UL,
  57. 42467986438630267UL, 50961583726356109UL, 61153900471627387UL,
  58. 73384680565952851UL, 88061616679143347UL, 105673940014972061UL,
  59. 126808728017966413UL, 152170473621559703UL, 182604568345871671UL,
  60. 219125482015045997UL, 262950578418055169UL, 315540694101666193UL,
  61. 378648832921999397UL, 454378599506399233UL, 545254319407679131UL,
  62. 654305183289214771UL, 785166219947057701UL, 942199463936469157UL,
  63. 1130639356723763129UL, 1356767228068515623UL, 1628120673682218619UL,
  64. 1953744808418662409UL, 2344493770102394881UL, 2813392524122873857UL,
  65. 3376071028947448339UL, 4051285234736937517UL, 4861542281684325481UL,
  66. 5833850738021191727UL, 7000620885625427969UL, 8400745062750513217UL,
  67. 10080894075300616261UL, 12097072890360739951UL, 14516487468432885797UL,
  68. 17419784962119465179UL,
  69. #endif
  70. SIZE_MAX /* sentinel, to ensure the search terminates */
  71. };
  72. /* Returns a suitable prime >= ESTIMATE. */
  73. static size_t
  74. next_prime (size_t estimate)
  75. {
  76. size_t i;
  77. for (i = 0; i < sizeof (primes) / sizeof (primes[0]); i++)
  78. if (primes[i] >= estimate)
  79. return primes[i];
  80. return SIZE_MAX; /* not a prime, but better than nothing */
  81. }