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Paper Version

by Yegor Bryukhov — last modified 2009-10-19 10:10

Instructions

The object of the game is to change one combination of letters into another by successively adding, inserting or deleting Rules one at a time. It is usually played with a pencil and paper, by listing the start letter(s) at the top, and the goal letter(s) at the bottom. A printable grid may be used as a work aid, but the grid has no relation to the length of any string of letters.

Change ba to bb

Rules: Ab, Ba, aA, Aa, bB, Bb

This puzzle can be solved in two steps:

Start with ba b a

Add Ab to ba to form baAb b a A b
Delete aA to form bb b b



Here are some games that you can  play with pencil and paper

    October 9, 2009

  1. Change AABABa to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 4 moves (printable grid, solution)
  2. Change AbAbabaaBa to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  3. Change baabAABAb an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid, solution)
  4. Change baBabAbaa to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid, solution)

    5. October 2, 2009

  5. Change an empty word to AABAba, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 4 moves (printable grid, solution)
  6. Change an empty word to AbAABABaBa, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  7. Change an empty word to ABAbABAB, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid, solution)
  8. Change babaBaba to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid, solution)

    9. September 25, 2009

  9. Change an empty word to baba, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  10. Change an empty word to AbAABAbaBa, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  11. Change an empty word to ABAbABAb, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid, solution)
  12. Change an empty word to baBaBaba, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid, solution)

    13. September 18, 2009

  13. Change an empty word to ABAB, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  14. Change AbAABAbaBa to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  15. Change ABAbABAb to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid, solution)
  16. Change baBaBaba to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid, solution)

    17. September 11, 2009

  17. Change baba to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  18. Change ABAABAbaba to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  19. Change empty word to baabAABAB, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid, solution)
  20. Change babaBAABABaB to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid, solution)

    21. September 3, 2009

  21. Change ABAb to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  22. Change AbabA to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  23. Change abAba to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid, solution)
  24. Change BAbaabaBAA to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid, solution)

    25. August 31, 2009

  25. Change ABAB to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  26. Change BAbaa to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  27. Change ABAbABAB to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid, solution)
  28. Change empty word to babAbABABab, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid, solution)

    29. July 24, 2009

  29. Change empty word to ABAb, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  30. Change ABAbabaaba to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  31. Change bAABAbABAbaB to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid, solution)
  32. Change babAABAbaabaBa to an empty word, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid)

    33. July 17, 2009

  33. Change cbABA to c, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid)
  34. Change c to cbABA, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid)
  35. Change cABaBaa to c, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 10 moves (printable grid)
  36. Change c to cABaBaa, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 20 moves (printable grid)

    37. July 9, 2009

  37. Change a to aaCABabcA, rules: aA,Aa,bB,Bb,cC,Cc,'aabbccc','CCCBBAA','ABab','BAba'; can be solved in 7 moves (printable grid, solution)
  38. Change a to acBabAC, rules: aA,Aa,bB,Bb,cC,Cc,'aabbccc','CCCBBAA','ABab','BAba'; can be solved in 7 moves (printable grid, solution)
  39. Change a to aabACbABacB, rules: aA,Aa,bB,Bb,cC,Cc,'aabbccc','CCCBBAA','ABab','BAba'; can be solved in 7 moves (printable grid, solution)

    40. July 4, 2009

  40. Change ccc to C, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; can be solved in 6 moves (printable grid, solution)
  41. Change a to BabCBABabbc, rules: aA,Aa,bB,Bb,cC,Cc,'aabbccc','CCCBBAA','ABab','BAba'; can be solved in 7 moves (printable grid, solution)
  42. Change a to aBABabbCABabc, rules: aA,Aa,bB,Bb,cC,Cc,'aabbccc','CCCBBAA','ABab','BAba'; can be solved in 23 moves (printable grid)
  43. Change BabaBBA to a, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; (printable grid, solution)

    44. June 26, 2009

  44. Change bd to db, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; can be solved in 4 moves (printable grid, solution)
  45. Change aaaaC to C, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; can be solved in 8 moves (printable grid, solution)
  46. Change abab to d, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; can be solved in 12 moves (printable grid, solution)
  47. Change abA to B, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; (printable grid, solution)

    48. June 19, 2009

  48. Change ad to da, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; can be solved in 4 moves (printable grid, solution)
  49. Change ab to c, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; can be solved in 8 moves (printable grid, solution)
  50. Change ab to bad, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; can be solved in 12 moves (printable grid, solution)
  51. Change ba to C, rules: aA,Aa,bB,Bb,cC,Cc,dD,Dd,aaD,bbD,ccD,dd,abcD; (printable grid, solution)

    52. June 12, 2009

  52. Change ba to AB, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  53. Change ABA to b, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 4 moves (printable grid, solution)
  54. Change ba to Ab, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 5 moves (printable grid, solution)
  55. Change aaba to baaa, rules: aA,Aa,bB,Bb,AbaB,bABa; (printable grid, it's a challenge game, send your solution to ybryukhov at-t-t ccny cuny edu)

    56. June 5, 2009

  56. Change ba to AB, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  57. Change ABA to b, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 4 moves (printable grid, solution)
  58. Change ba to Ab, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 5 moves (printable grid, solution)
  59. Change aaba to baaa, rules: aA,Aa,bB,Bb,AbaB,bABa; (printable grid, solution)

    60. May 29, 2009

  60. Change abab to BABA, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 2 moves (printable grid, solution)
  61. Change AA to a, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  62. Change aaaABB to b, rules: aA,Aa,bB,baa,bb,AAB,BB; can be solved in 11 moves (printable grid, solution)

    63. May 22, 2009

  63. Change ab to ba, rules: aA,Aa,bB,Bb,baa,bb,AAB,BB; can be solved in 4 moves (printable grid, solution)
  64. Change aaaaB to B, rules: aA,Aa,bB,Bb,baa,bb,AAB,BB; can be solved in 5 moves (printable grid, solution)
  65. Change babbbabaB to A, rules: aA,Aa,bB,baa,bb,AAB,BB; can be solved in 11 moves (printable grid, solution)
  66. Change aBaBaB to bA, rules: aA,Aa,bB,Bb,aa,bb,abab,AA,BB,BABA; (printable grid, solution)

    67. May 15, 2009

  67. Change ab to BA, rules: aA,Aa,bB,Bb,aa,bb,abab,AA,BB,BABA; can be solved in 3 moves (printable grid, solution)
  68. Change ABA to b, rules: aA,Aa,bB,Bb,aa,bb,abab,AA,BB,BABA; can be solved in 4 moves (printable grid, solution)
  69. Change baba to ABAB, rules: aA,Aa,bB,Bb,aa,bb,abab,AA,BB,BABA; can be solved in 6 moves (printable grid, solution)
  70. Change aBaBaB to bA, rules: aA,Aa,bB,Bb,aaa,bb,abab,AAA,BB,BABA; can be solved in 12 moves(printable grid, solution)

    71. May 8, 2009

  71. Change aba to B, rules: aA,Aa,bB,Bb,aa,bb,abab,AA,BB,BABA; can be solved in 2 moves (printable grid, solution)
  72. Change Ab to bbA, rules: AbaBB,bbABa,aA,Aa,bB,Bb; can be solved in 3 moves (printable grid, solution)
  73. Change ab to ba, rules: aA,Aa,bB,Bb,aa,bb,abab,AA,BB,BABA; can be solved in 7 moves (printable grid, solution)
  74. Change Ba to aB, rules: ababa,ABABA,aA,Aa,bB,Bb; (printable grid, solution)

    75. May 1, 2009

  75. Change aa to A, rules: aaa, AAA, aA, Aa; can be solved in 2 moves (printable grid, solution)
  76. Change BAb to bA, rules: AbaBB, bbABa, Aa, aA, Bb, bB; can be solved in 6 moves (printable grid, solution)
  77. Change ba to ab, rules: ababa, ABABA, Aa, aA, Bb, bB; can be solved in 7 moves (printable grid, solution)
  78. Change aBA to Ab, rules: Aa, aA, Bb, bB, aaa, bb, abab, AAA, BB, BABA; can be solved in 5 moves (printable grid, solution)

    79. Practice games (the easy games first):

  79. Change a to A, rules: aa, AA, aA, Aa; can be solved in 2 moves (printable grid, solution)
  80. Change ab to ba, rules: aa, AA, bb, BB, abab, BABA, aA, Aa, bB, Bb; can be solved in 3 moves (printable grid, solution)
  81. Change ab to ba, rules: aB, bA, aA, Aa, bB, Bb; can be solved in 4 moves (printable grid, solution)
  82. Change aba to B, rules: BaBa, AbAb, aa, AA, aA, Aa, bB, Bb; can be solved in 4 moves (printable grid, solution)
  83. Change cba to abc, rules: Ab, Ba, Ac, Ca, Bc, Cb, aa, AA, aA, Aa, bB, Bb, cC, Cc; can be solved in 4 moves (printable grid, solution)
  84. Change abbA to b, rules: AbaBB, bbABa, aA, Aa, bB, Bb; can be solved in 5  moves (printable grid, solution)
  85. Change AbBaAcCa to bB, rules: aA, Aa, bB, Bb, cC, Cc; can be solved in 5 moves (printable grid, solution)
  86. Change aaa to bbb, rules: aB, bA, Ab, Ba, aA, Aa, bB, Bb; can be solved in 6 moves (printable grid, solution)
  87. Change abab to baba, rules: aB, bA, Ab, Ba, aA, Aa, bB, Bb; can be solved in 8 moves (printable grid, solution)
 

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