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  1. PRIM┼á i≤ thσ primσ numbe≥ teste≥ illustrateΣ iε thσ Jaε 8│ issuσ ì
  2. oµ BYTE«  ╔ diΣ u≡ encrypt¼ decryp⌠ anΣ thσ ke∙ generato≥ a≤ wel∞ ì
  3. bu⌠ aφ no⌠ submittinτ theφ a≤ decryp⌠ wil∞ no⌠ worδ properl∙á anΣ ì
  4. thσá systeφá i≤ no⌠ practica∞ duσ t∩ speeΣá limitations«á  Anyonσ ì
  5. reall∙á wantinτ m∙ worδ caε writσ mσ directly..«á  Followinτá arσ ì
  6. somσ lesson≤ learned.
  7.  
  8. ╔á useΣá thσá informatioε iε thσ Bytσ articlσá t∩á ge⌠á ßá systeφ ì
  9. runninτ tha⌠ encrypted/decrypteΣ wholσ file≤ insteaΣ oµ line≤ anΣ ì
  10. blocks«á  ╔ raε thi≤ u≡ iε Microsof⌠ BASI├ oε thσ machinσ a⌠ worδ ì
  11. whicΦá ha≤á aε 8086«á  Duσ t∩ speeΣ problems¼á eveε oε tha⌠á 8mh· ì
  12. machine¼á ╔ lookeΣ fo≥ severa∞ alternatives¼ particularl∙ fo≥ thσ ì
  13. decryptioε algorithm«  Oµ thσ language≤ available¼ onl∙ BASI├ haΣ ì
  14. extendeΣ precisioε arithmetic..«á  ╔ exploreΣ thσ possibilit∙á oµ ì
  15. usinτá thσ FIXE─ routine≤ supplieΣ b∙ Ithaca¼á bu⌠ founΣá severa∞ ì
  16. unexplaineΣá bugs«á  Als∩ go⌠ onσ fi° froφ Ithaca¼á bu⌠ i⌠ didn'⌠ ì
  17. hel≡á ß lot«á  Theε ╔ discovereΣ thσ UNIT▒ stufµ iεá thσá librar∙ ì
  18. disc«á  Thσá 808╢ machinσ ha≤ ß Pasca∞ compile≥ oε it¼á bu⌠ i⌠ i≤ ì
  19. wierΣ -- filσ I/╧ i≤ eveε worsσ thaε Zíá  Bu⌠ thσ UNIT▒ stufµá i≤ ì
  20. fairly standard Pascal and should be portable...
  21.  
  22. UNIT▒á i≤ nicel∙ implementeΣ anΣ commented«á  ╔ founΣ ver∙ littlσ ì
  23. troublσ makinτ thσ routine≤ work«á  The∙ i≤ al∞ se⌠ u≡ fo≥ usσ a≤ ì
  24. externall∙á compileΣ files«á Thσ strateg∙ oµ stabilizinτ thσ maiε ì
  25. prograφ earl∙ anΣ puttinτ al∞ thσ worδ iε aε externa∞ filσ reall∙ ì
  26. pay≤ off«  UNIT▒ i≤ ß BI╟ se⌠ oµ procedure≤ anΣ yo⌡ don'⌠ wan⌠ t∩ ì
  27. recompilσá anΣ reassemblσ i⌠ an∙ morσ thaεá necessary(watcΦá you≥ ì
  28. disπ space).
  29.  
  30. The assets to UNIT1 are:
  31.      - al∞ se⌠ u≡ t∩ implement«á  Eveε ß dumm∙ likσ mσ caε figurσ ì
  32. it out and get things to run.
  33.      - intege≥ arithmetic¼ completσ witΦ DI╓ anΣ MO─ function≤ i≤ ì
  34. implemented.  
  35.  
  36. Thσá chieµ drawbacδ≤áare: ì
  37.      - routine≤ lacδ thσ abilit∙ t∩ translatσ bacδ t∩ string≤á o≥ ì
  38. reals
  39.      - the∙á reall∙ slo≈ thing≤ down«á  Interprete≥ BASI├á doublσ ì
  40. precision is much faster.
  41.      - yo⌡ ge⌠ fifteen¼á no⌠ 1╢ digits¼á oµ precision«á  Thi≤ raε ì
  42. the decrypt program aground.
  43.      - fo≥ somσ unexplaineΣ reason¼ thσ getlonτ procedurσ mus⌠ bσ ì
  44. followed by 2 carriage returns...
  45.  
  46. I carried things this far for some other reasons:
  47.      - I wanted to wring out the UNIT1 features.
  48.      - Maybσ somσ oµ yo⌡ caε ge⌠ somσ valuσ froφ m∙ work«á  UNIT▒ ì
  49. is not very noticable in the library, but pretty nifty.
  50.  
  51. Bσá prepareΣá t∩ watcΦ ß ver∙ dumΓ prograφ fo≥ ß ver∙ lonτá timeí  ì
  52. Fo≥ thσ BASI├ versioε a⌠ work¼ ╔ modifieΣ thσ prograφ t∩ loτ gooΣ ì
  53. primσ number≤ t∩ ß disc¼á closσ thσ filσ anΣ kee≡ running«á  Tha⌠ ì
  54. wa∙á yo⌡ star⌠ thσ prograφ anΣ g∩ home«á  I⌠ take≤ ß ^π t∩á breaδ ì
  55. thσ program(makσ surσ thσ filσ i≤ closeΣ s∩ yo⌡ don'⌠ losσ it).