Statistics

Problem Statement for "WolfDelaymaster"

Problem Statement

Wolf Sothe is playing the game Delaymaster. In this game, he can create new words according to the following rules:
  1. For each positive integer n, the string which consists of n copies of 'w', then n copies of 'o', then n copies of 'l', and finally n copies of 'f' is a valid word.
  2. The concatenation of two valid words is a valid word.
  3. Only the words that can be obtained by rules 1 and 2 are valid. There are no other valid words.
Thus, for example:
  • By rule 1, "wolf", "wwoollff", and "wwwooolllfff" are valid words.
  • Then, by rule 2, "wolfwwoollff" is a valid word.
  • By applying rule 2 twice, "wolfwwoollffwolf" is a valid word.
  • The string "wfol" is not a valid word (order matters).
  • The string "wwolfolf" is not a valid word (we can only concatenate, not insert one word into another).
  • The string "wwwoolllfff" is not a valid word (only two 'o's instead of three).
You are given a String str. Return "VALID" if str is a valid word and "INVALID" otherwise. Note that the return value is case-sensitive: you must return the strings "VALID" and "INVALID" in all-uppercase.

Definition

Class:
WolfDelaymaster
Method:
check
Parameters:
String
Returns:
String
Method signature:
String check(String str)
(be sure your method is public)

Constraints

  • str will contain between 1 and 50 characters, inclusive.
  • Each character in str will be 'w', 'o', 'l' or 'f'.

Examples

  1. "wolf"

    Returns: "VALID"

    The first valid word from the examples in the problem statement.

  2. "wwolfolf"

    Returns: "INVALID"

    The second invalid word from the examples in the problem statement.

  3. "wolfwwoollffwwwooolllfffwwwwoooollllffff"

    Returns: "VALID"

  4. "flowolf"

    Returns: "INVALID"

  5. "o"

    Returns: "INVALID"

  6. "fo"

    Returns: "INVALID"

  7. "lfw"

    Returns: "INVALID"

  8. "llwl"

    Returns: "INVALID"

  9. "ofwff"

    Returns: "INVALID"

  10. "fwwloo"

    Returns: "INVALID"

  11. "llwolow"

    Returns: "INVALID"

  12. "flffwwff"

    Returns: "INVALID"

  13. "lllfoffff"

    Returns: "INVALID"

  14. "ffwffwwoow"

    Returns: "INVALID"

  15. "wflolwfolwo"

    Returns: "INVALID"

  16. "wlwwlfolflow"

    Returns: "INVALID"

  17. "ofwwoooffwlll"

    Returns: "INVALID"

  18. "wwfwfllwowolfl"

    Returns: "INVALID"

  19. "ollooolwoofwwwf"

    Returns: "INVALID"

  20. "ooffwffflfwlwwol"

    Returns: "INVALID"

  21. "wofowlwlolllfolof"

    Returns: "INVALID"

  22. "llfoowfoofffooolof"

    Returns: "INVALID"

  23. "wlwwwflwfoolwwwwwol"

    Returns: "INVALID"

  24. "wlwofwfwlfffowollofo"

    Returns: "INVALID"

  25. "ofowfffwllooooflowfwl"

    Returns: "INVALID"

  26. "owwoolwowfwlflllwwlwol"

    Returns: "INVALID"

  27. "wlowloffowoowwofwlwwlol"

    Returns: "INVALID"

  28. "wolwllloloolfowoffolwlfo"

    Returns: "INVALID"

  29. "lflwfoolowoofwwffooffflwo"

    Returns: "INVALID"

  30. "wowflwfofloolwoolwwflflflo"

    Returns: "INVALID"

  31. "olwllfofofowwfofofofwwoffof"

    Returns: "INVALID"

  32. "llfollfloowllwfllolfoloflflo"

    Returns: "INVALID"

  33. "owloowllowfofwowowfllfflfoool"

    Returns: "INVALID"

  34. "owfwllwfwloolwfwlwofwowoowwffl"

    Returns: "INVALID"

  35. "owoofffwoloffwooflolwlwwfofoflo"

    Returns: "INVALID"

  36. "oowlooolwwfwwfwfowloolwllowoffwl"

    Returns: "INVALID"

  37. "owlwlfollfwwfoffololwfoowlwloflof"

    Returns: "INVALID"

  38. "ofolowlwwoowfowlfwowwwowoofoolwlff"

    Returns: "INVALID"

  39. "lowwffllwlofllwwwfwowofoowlolfloowo"

    Returns: "INVALID"

  40. "wfollwlwoolwlolwowloowlflfwfwofflfow"

    Returns: "INVALID"

  41. "olfowwwflofowlwwofofwwoowowlfwllfwflf"

    Returns: "INVALID"

  42. "oowfflloowwolwwwlfwofoolwwwwwwfwfffowo"

    Returns: "INVALID"

  43. "wolfwlfwllfoofofllfwffwfowwfowflfflolll"

    Returns: "INVALID"

  44. "wolffwlfllfflwlowwwlwoffflowflfwfowwoooo"

    Returns: "INVALID"

  45. "loofwwwfooolffwlwoowwwwwfoofwowwollffowoo"

    Returns: "INVALID"

  46. "oofoolllowwlfllofwofwfololllflflfoollwwflo"

    Returns: "INVALID"

  47. "loooofwfflwwflolloolofwfoowlwolfwfowwllwooo"

    Returns: "INVALID"

  48. "wlolfwfffflffwfowfowlfwwwolowolfolwolffofwfo"

    Returns: "INVALID"

  49. "wlwoloolooffowwwlwwowlwoflflwwlwlflfoowlfowow"

    Returns: "INVALID"

  50. "offwllfllffwlwlffwowfwwlolooofolofwoolwwlfoooo"

    Returns: "INVALID"

  51. "wfolwwlwolwfffwofoffowlolflfoffoofolfwfwolflwwl"

    Returns: "INVALID"

  52. "woffffllfowwlfwffloffooolfoflfflfflwfoflfffowlfl"

    Returns: "INVALID"

  53. "folfffolwlllowwlllloloowlllfwooowlwwwfwlllllooolo"

    Returns: "INVALID"

  54. "fofflwllwooowowwwllllwlwllwwlwwfwwfwofwwfolowlolwo"

    Returns: "INVALID"

  55. "wwwwwwwwwwwwoooooooooooollllllllllllffffffffffff"

    Returns: "VALID"

  56. "wwwwoooollllffffwwwwwwwooooooolllllllfffffff"

    Returns: "VALID"

  57. "wwwwwwwwwwoooooooooollllllllllffffffffff"

    Returns: "VALID"

  58. "wwwwoooollllffffwwwwwwwwoooooooollllllllffffffff"

    Returns: "VALID"

  59. "wwwooolllfffwwwwoooollllffffwwwwoooollllffff"

    Returns: "VALID"

  60. "wwwwwwwwwooooooooolllllllllfffffffff"

    Returns: "VALID"

  61. "wwoollffwwoollffwwoollffwwwwwooooolllllfffff"

    Returns: "VALID"

  62. "wwwwwwwwwooooooooolllllllllfffffffff"

    Returns: "VALID"

  63. "wwwwwwwwwwoooooooooollllllllllffffffffff"

    Returns: "VALID"

  64. "wwoollffwwwwoooollllffffwolf"

    Returns: "VALID"

  65. "wwwwwooooolllllfffff"

    Returns: "VALID"

  66. "wwwwwwwwwooooooooolllllllllfffffffffwolf"

    Returns: "VALID"

  67. "wwwwoooollllffff"

    Returns: "VALID"

  68. "wwwwwwwwoooooooollllllllffffffff"

    Returns: "VALID"

  69. "wwwwwooooolllllfffffwolfwwwwwwoooooollllllffffff"

    Returns: "VALID"

  70. "wwwwwwwooooooolllllllfffffff"

    Returns: "VALID"

  71. "wwwwwooooolllllfffffwwoollff"

    Returns: "VALID"

  72. "wwwwwwoooooollllllffffffwwwooolllfff"

    Returns: "VALID"

  73. "wwwwoooollllffffwwwwwwoooooollllllffffff"

    Returns: "VALID"

  74. "wwwwwwwwwwoooooooooollllllllllffffffffff"

    Returns: "VALID"

  75. "wwwwwooooolllllfffffwwwooolllfffwwoollff"

    Returns: "VALID"

  76. "wwwwwwoooooollllllffffffwolfwwwwwooooolllllfffff"

    Returns: "VALID"

  77. "wwwwwwoooooollllllffffffwwwwoooollllffff"

    Returns: "VALID"

  78. "wwwwoooollllffffwwwooolllfffwwwwwooooolllllfffff"

    Returns: "VALID"

  79. "wwwwwwwwwwoooooooooollllllllllffffffffffwwoollff"

    Returns: "VALID"

  80. "wwoollffwwwwwwwwoooooooollllllllffffffff"

    Returns: "VALID"

  81. "wolfwwwwwwwwoooooooollllllllffffffffwwoollff"

    Returns: "VALID"

  82. "wwwwwwoooooollllllffffffwwwooolllfff"

    Returns: "VALID"

  83. "wwwooolllfffwwwwwwoooooollllllffffffwwoollff"

    Returns: "VALID"

  84. "wwwwwwwwwooooooooolllllllllfffffffff"

    Returns: "VALID"

  85. "wwwwwooooolllllfffffwwwwwwwooooooolllllllfffffff"

    Returns: "VALID"

  86. "wwoollffwwwwwwwwwwoooooooooollllllllllffffffffff"

    Returns: "VALID"

  87. "wwwooolllfff"

    Returns: "VALID"

  88. "wwwwwwwooooooolllllllfffffffwwwooolllfff"

    Returns: "VALID"

  89. "wwoollffwwwwwwwwwooooooooolllllllllfffffffff"

    Returns: "VALID"

  90. "wwwwwwwooooooolllllllfffffff"

    Returns: "VALID"

  91. "wolfwwoollffwwwwoooollllffffwwwwwooooolllllfffff"

    Returns: "VALID"

  92. "wwwooolllfffwwoollff"

    Returns: "VALID"

  93. "wwwwwwwwoooooooollllllllffffffff"

    Returns: "VALID"

  94. "wwwooolllfffwwwwwwwwwooooooooolllllllllfffffffff"

    Returns: "VALID"

  95. "wwwwwooooolllllfffff"

    Returns: "VALID"

  96. "wwwooolllfffwwwooolllfff"

    Returns: "VALID"

  97. "wwwwwooooolllllfffffwwwwwwwooooooolllllllfffffff"

    Returns: "VALID"

  98. "wwwwwwwwwooooooooolllllllllfffffffffwolf"

    Returns: "VALID"

  99. "wwoollffwwwwoooollllffff"

    Returns: "VALID"

  100. "wwwwwooooolllllfffffwwwooolllfff"

    Returns: "VALID"

  101. "wwwooolllfffwwwwwwoooooollllllffffffwwoollff"

    Returns: "VALID"

  102. "wwwwwooooolllllfffffwwoollff"

    Returns: "VALID"

  103. "wwwwwwwwoooooooollllllllffffffff"

    Returns: "VALID"

  104. "wwoollffwwoollff"

    Returns: "VALID"

  105. "wwoollffwwwwwwoooooollllllffffffwwwooolllfff"

    Returns: "VALID"

  106. "wwwooolllff"

    Returns: "INVALID"

  107. "wwoollfff"

    Returns: "INVALID"

  108. "ffwwooll"

    Returns: "INVALID"

  109. "wolfwolf"

    Returns: "VALID"

  110. "wolfwolfwwoollffwolfwwwooolllff"

    Returns: "INVALID"

  111. "wofl"

    Returns: "INVALID"

  112. "wolfwol"

    Returns: "INVALID"

  113. "wol"

    Returns: "INVALID"

  114. "wwooollllllfff"

    Returns: "INVALID"

  115. "w"

    Returns: "INVALID"

  116. "wlof"

    Returns: "INVALID"

  117. "wolfwwwwww"

    Returns: "INVALID"

  118. "wolff"

    Returns: "INVALID"

  119. "llll"

    Returns: "INVALID"

  120. "wwolf"

    Returns: "INVALID"

  121. "wlofwlof"

    Returns: "INVALID"

  122. "wo"

    Returns: "INVALID"

  123. "woowllff"

    Returns: "INVALID"

  124. "wwoollff"

    Returns: "VALID"

  125. "wwwwwwwww"

    Returns: "INVALID"

  126. "fwolf"

    Returns: "INVALID"

  127. "flwo"

    Returns: "INVALID"

  128. "ooo"

    Returns: "INVALID"

  129. "flow"

    Returns: "INVALID"

  130. "wwwww"

    Returns: "INVALID"

  131. "wwolfwoolfwollfwolff"

    Returns: "INVALID"

  132. "wwwwoooollllf"

    Returns: "INVALID"

  133. "wwww"

    Returns: "INVALID"

  134. "fwol"

    Returns: "INVALID"

  135. "wwwwwooooolllllfffffwwwolfwwooooooolllllllfffffff"

    Returns: "INVALID"

  136. "wwolfwoollff"

    Returns: "INVALID"

  137. "wolfwoolfwwollff"

    Returns: "INVALID"

  138. "wowollff"

    Returns: "INVALID"

  139. "wolfwo"

    Returns: "INVALID"

  140. "olfw"

    Returns: "INVALID"

  141. "wwwwwwww"

    Returns: "INVALID"

  142. "wollfwwoolff"

    Returns: "INVALID"

  143. "woolf"

    Returns: "INVALID"

  144. "wfol"

    Returns: "INVALID"

  145. "wolfw"

    Returns: "INVALID"

  146. "llffwwoo"

    Returns: "INVALID"

  147. "oolf"

    Returns: "INVALID"

  148. "wwwolllllllf"

    Returns: "INVALID"

  149. "wwoollf"

    Returns: "INVALID"

  150. "wwwwooollff"

    Returns: "INVALID"

  151. "wwwwwolf"

    Returns: "INVALID"

  152. "wwfollof"

    Returns: "INVALID"

  153. "wwwoollllffffff"

    Returns: "INVALID"

  154. "ww"

    Returns: "INVALID"

  155. "wolfwolfwwolf"

    Returns: "INVALID"

  156. "wwwwww"

    Returns: "INVALID"

  157. "wwwolfoollff"

    Returns: "INVALID"

  158. "wwllooff"

    Returns: "INVALID"

  159. "olfwolf"

    Returns: "INVALID"

  160. "wolfl"

    Returns: "INVALID"

  161. "wolfwwoo"

    Returns: "INVALID"

  162. "wolw"

    Returns: "INVALID"

  163. "wwowoolllfff"

    Returns: "INVALID"

  164. "www"

    Returns: "INVALID"

  165. "wolllfff"

    Returns: "INVALID"

  166. "wolfwwwwoooollllff"

    Returns: "INVALID"

  167. "wwwoollffwoollff"

    Returns: "INVALID"

  168. "woolllfff"

    Returns: "INVALID"

  169. "wlfo"

    Returns: "INVALID"

  170. "wolffwol"

    Returns: "INVALID"

  171. "wolwolff"

    Returns: "INVALID"

  172. "wwooollffwwollff"

    Returns: "INVALID"

  173. "wolfwwoollffwwwooolllfffwwwwoooollllfff"

    Returns: "INVALID"

  174. "woollf"

    Returns: "INVALID"

  175. "oooo"

    Returns: "INVALID"

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