Problem Name | Online Judge | Year | Contest | Difficulty Level | |
---|---|---|---|---|---|

1 | k-String | Codeforces | Codeforces Round #135 (Div. 2) | 1 | |

2 | Dubstep | Codeforces | Codeforces Round #130 (Div. 2) | 1 | |

3 | Amusing Joke | Codeforces | Codeforces Round #101 (Div. 2) | 1 | |

4 | String Task | Codeforces | Codeforces Beta Round #89 (Div. 2) | 1 | |

5 | Petya and Strings | Codeforces | Codeforces Beta Round #85 (Div. 2 Only) | 1 | |

6 | Football | Codeforces | Codeforces Beta Round #77 (Div. 2 Only) | 1 | |

7 | Way Too Long Words | Codeforces | Codeforces Beta Round #65 (Div. 2) | 1 | |

8 | Word | Codeforces | Codeforces Beta Round #55 (Div. 2) | 1 | |

9 | Chat room | Codeforces | Codeforces Beta Round #54 (Div. 2) | 1 | |

10 | Football | Codeforces | Codeforces Beta Round #42 (Div. 2) | 1 | |

11 | Translation | Codeforces | Codeforces Beta Round #40 (Div. 2) | 1 | |

12 | What's Cryptanalysis? | UVA | 1 | ||

13 | To Carry or not to Carry | UVA | 1 | ||

14 | Mother bear | UVA | 1 | ||

15 | Party Games | Live Archive | 2012 | North America - Mid-Atlantic USA | 1 |

16 | Glass Beads | SPOJ | 1 | ||

17 | One-Two-Three | UVA | 1 | ||

18 | Decode the tape | UVA | 1 | ||

19 | A+B Problem | PKU | 1 | ||

20 | Power Strings | UVA | 1 | ||

21 | LetterStrings | TopCoder | SRM 202 - Div2 easy] (5848) | 1 | |

22 | Watermelon | Codeforces | Codeforces Beta Round #4 (Div. 2 Only) | 1 | |

23 | String Cutting | Live Archive | 2006 | Asia - Hanoi | 1 |

24 | Two Substrings | Codeforces | Codeforces Round #306 (Div. 2) | 1 | |

25 | Pangram | Codeforces | Codeforces Round #295 (Div. 2) | 1 | |

26 | Misha and Changing Handles | Codeforces | Codeforces Round #285 (Div. 2) | 1 | |

27 | Lecture | Codeforces | Codeforces Round #284 (Div. 2) | 1 | |

28 | Suffix Structures | Codeforces | Codeforces Round #256 (Div. 2) | 1 | |

29 | Helpful Maths | Codeforces | Codeforces Round #197 (Div. 2) | 1 | |

30 | Word Capitalization | Codeforces | Codeforces Round #172 (Div. 2) | 1 | |

31 | cAPS lOCK | Codeforces | Codeforces Beta Round #95 (Div. 2) | 1 | |

32 | Different is Good | Codeforces | Codeforces Round #352 (Div. 2) | 1 | |

33 | Flip Sort | UVA | 1 | ||

34 | Hongcow Learns the Cyclic Shift | Codeforces | Codeforces Round #385 (Div. 2) | 1 | |

35 | Ostap and Grasshopper | Codeforces | Codeforces Round #382 (Div. 2) | 1 | |

36 | Mahmoud and Longest Uncommon Subsequence | Codeforces | Codeforces Round #396 (Div. 2) | 1 | |

37 | Mike and palindrome | Codeforces | Codeforces Round #410 (Div. 2) | 1 | |

38 | Passwords | Codeforces | Codeforces Round #374 (Div. 2) | 1 | |

39 | Powers Et Al. | UVA | 1 | ||

40 | Little Elephant and Chess | Codeforces | Codeforces Round #157 (Div. 2) | 2 | |

41 | Comparing Strings | Codeforces | Codeforces Round #118 (Div. 2) | 2 | |

42 | Another Problem on Strings | Codeforces | Codeforces Round #112 (Div. 2) | 2 | |

43 | Password | Codeforces | Codeforces Beta Round #93 (Div. 1 Only) & Codeforces Beta Round #93 (Div. 2 Only) | 2 | |

44 | Palindromic Times | Codeforces | Codeforces Beta Round #83 (Div. 2 Only) | 2 | |

45 | Restoring Password | Codeforces | Codeforces Beta Round #76 (Div. 2 Only) | 2 | |

46 | Sinking Ship | Codeforces | Codeforces Beta Round #59 (Div. 2) | 2 | |

47 | Message Decoding | UVA | 2 | ||

48 | Uncompress | UVA | 2 | ||

49 | Chuỗi từ | SPOJ Vietnam | 2 | ||

50 | Combination | Codeforces | Codeforces Round #109 (Div. 2) | 2 | |

51 | Strings of Power | Codeforces | Codeforces Round #188 (Div. 2) | 2 | |

52 | Pattern Finder | Live Archive | 2008 | South Pacific | 2 |

53 | Strings with Same Letters | A2 Online Judge | 2 | ||

54 | War of the Corporations | Codeforces | Codeforces Round #342 (Div. 2) | 2 | |

55 | Comparing Two Long Integers | Codeforces | Educational Codeforces Round 5 | 2 | |

56 | Queries on a String | Codeforces | Educational Codeforces Round 1 | 2 | |

57 | Equivalent Strings | Codeforces | Codeforces Round #313 (Div. 1) & Codeforces Round #313 (Div. 2) | 2 | |

58 | Ohana Cleans Up | Codeforces | Codeforces Round #309 (Div. 2) | 2 | |

59 | Tanya and Postcard | Codeforces | Codeforces Round #293 (Div. 2) | 2 | |

60 | Vitaly and Strings | Codeforces | Codeforces Round #293 (Div. 2) | 2 | |

61 | Mr. Kitayuta's Gift | Codeforces | Codeforces Round #286 (Div. 1) & Codeforces Round #286 (Div. 2) & Codeforces Round #286 (Div. 1) & Codeforces Round #286 (Div. 2) | 2 | |

62 | Hacking Cypher | Codeforces | Codeforces Round #279 (Div. 2) | 2 | |

63 | Eevee | Codeforces | MemSQL Start[c]UP 2.0 - Round 1 | 2 | |

64 | Bear and Strings | Codeforces | Codeforces Round #226 (Div. 2) | 2 | |

65 | String Game | Codeforces | Codeforces Round #402 (Div. 1) & Codeforces Round #402 (Div. 2) | 2 | |

66 | Valued Keys | Codeforces | Codeforces Round #409 (rated, Div. 2, based on VK Cup 2017 Round 2) | 2 | |

67 | Mike and strings | Codeforces | Codeforces Round #410 (Div. 2) | 2 | |

68 | Anagram String | A2 Online Judge | 2 | ||

69 | Find the Format String | Live Archive | 2008 | Asia - Dhaka | 2 |

70 | Internet Address | Codeforces | CROC-MBTU 2012, Elimination Round (ACM-ICPC) | 3 | |

71 | LLPS | Codeforces | Codeforces Round #127 (Div. 2) | 3 | |

72 | Common Divisors | Codeforces | Codeforces Round #117 (Div. 2) | 3 | |

73 | Lucky String | Codeforces | Codeforces Beta Round #84 (Div. 2 Only) | 3 | |

74 | Help Far Away Kingdom | Codeforces | Codeforces Beta Round #78 (Div. 2 Only) | 3 | |

75 | Haiku | Codeforces | Codeforces Beta Round #70 (Div. 2) | 3 | |

76 | Petya and Java | Codeforces | Codeforces Beta Round #61 (Div. 2) | 3 | |

77 | Letter | Codeforces | Codeforces Beta Round #42 (Div. 2) | 3 | |

78 | Longest Regular Bracket Sequence | Codeforces | Codeforces Beta Round #5 | 3 | |

79 | Phone Numbers | Codeforces | Codeforces Round #107 (Div. 2) | 3 | |

80 | Tin mật | SPOJ Vietnam | 3 | ||

81 | Known Plaintext Attack | UVA | 3 | ||

82 | Secret Word | UVA | 3 | ||

83 | Simple Strings | Codeforces | Educational Codeforces Round 12 | 3 | |

84 | Bear and Compressing | Codeforces | IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) | 3 | |

85 | The Text Splitting | Codeforces | Educational Codeforces Round 4 | 3 | |

86 | DNA Alignment | Codeforces | Codeforces Round #295 (Div. 2) & Codeforces Round #295 (Div. 1) | 3 | |

87 | Watto and Mechanism | Codeforces | Codeforces Round #291 (Div. 2) | 3 | |

88 | No to Palindromes! | Codeforces | Codeforces Round #265 (Div. 1) & Codeforces Round #265 (Div. 2) | 3 | |

89 | Good Substrings | Codeforces | Codeforces Round #166 (Div. 2) | 3 | |

90 | Friendly Int Parser | URI | 3 | ||

91 | Cloud of Hashtags | Codeforces | Codeforces Round #401 (Div. 2) | 3 | |

92 | Mahmoud and a Message | Codeforces | Codeforces Round #396 (Div. 2) | 3 | |

93 | Prime Palindrome | A2 Online Judge | 3 | ||

94 | Whose sentence is it? | Codeforces | Codeforces Round #185 (Div. 2) | 3 | |

95 | Queries for Number of Palindromes | Codeforces | CROC-MBTU 2012, Elimination Round (ACM-ICPC) | 4 | |

96 | Palindrome pairs | Codeforces | VK Cup 2012 Qualification Round 2 | 4 | |

97 | String Manipulation 1.0 | Codeforces | VK Cup 2012 Qualification Round 2 | 4 | |

98 | Anagram Search | Codeforces | Codeforces Round #103 (Div. 2) | 4 | |

99 | Help Kingdom of Far Far Away 2 | Codeforces | Codeforces Round #102 (Div. 2) | 4 | |

100 | Hard Work | Codeforces | Codeforces Beta Round #57 (Div. 2) | 4 | |

101 | Choosing Symbol Pairs | Codeforces | Codeforces Beta Round #47 | 4 | |

102 | Page Numbers | Codeforces | Codeforces Beta Round #34 (Div. 2) | 4 | |

103 | Train and Peter | Codeforces | Codeforces Beta Round #8 | 4 | |

104 | Center Alignment | Codeforces | Codeforces Beta Round #5 | 4 | |

105 | Matrix Matcher | UVA | 4 | ||

106 | Dinner | SPOJ | 4 | ||

107 | The Smallest String Concatenation | Codeforces | Educational Codeforces Round 9 | 4 | |

108 | ZgukistringZ | Codeforces | Codeforces Round #307 (Div. 2) | 4 | |

109 | Tavas and Malekas | Codeforces | Codeforces Round #299 (Div. 2) & Codeforces Round #299 (Div. 1) | 4 | |

110 | MUH and Cube Walls | Codeforces | Codeforces Round #269 (Div. 2) | 4 | |

111 | A Lot of Games | Codeforces | Codeforces Round #260 (Div. 1) & Codeforces Round #260 (Div. 2) | 4 | |

112 | Prefixes and Suffixes | Codeforces | Codeforces Round #246 (Div. 2) | 4 | |

113 | Pattern | Codeforces | Coder-Strike 2014 - Round 1 | 4 | |

114 | Dima and Text Messages | Codeforces | Codeforces Round #208 (Div. 2) | 4 | |

115 | Command Line Arguments | Codeforces | Croc Champ 2013 - Qualification Round | 4 | |

116 | New Problem | Codeforces | Codeforces Round #170 (Div. 2) | 4 | |

117 | Ancient Prophesy | Codeforces | Codeforces Round #158 (Div. 2) | 4 | |

118 | African Crossword | Codeforces | Codeforces Beta Round #74 (Div. 2 Only) | 4 | |

119 | Omar's Bug | A2 Online Judge | 4 | ||

120 | Punctuation | Codeforces | Codeforces Testing Round #4 | 5 | |

121 | Prime Permutation | Codeforces | Codeforces Beta Round #92 (Div. 1 Only) & Codeforces Beta Round #92 (Div. 2 Only) | 5 | |

122 | Lucky Transformation | Codeforces | Codeforces Beta Round #91 (Div. 1 Only) & Codeforces Beta Round #91 (Div. 2 Only) | 5 | |

123 | Fancy Number | Codeforces | Codeforces Beta Round #89 (Div. 2) | 5 | |

124 | Petr# | Codeforces | Codeforces Beta Round #86 (Div. 1 Only) & Codeforces Beta Round #86 (Div. 2 Only) | 5 | |

125 | Grammar Lessons | Codeforces | Codeforces Beta Round #86 (Div. 1 Only) & Codeforces Beta Round #86 (Div. 2 Only) | 5 | |

126 | Newspaper Headline | Codeforces | Codeforces Beta Round #75 (Div. 1 Only) & Codeforces Beta Round #75 (Div. 2 Only) | 5 | |

127 | Sequence Formatting | Codeforces | Yandex.Algorithm Open 2011 Qualification 1 | 5 | |

128 | Facetook Priority Wall | Codeforces | Codeforces Beta Round #67 (Div. 2) | 5 | |

129 | Sysadmin Bob | Codeforces | Codeforces Beta Round #31 (Div. 2, Codeforces format) | 5 | |

130 | Palindrome Degree | Codeforces | Codeforces Beta Round #7 | 5 | |

131 | GuessTheSubstring | TopCoder | TCO11 Semifinal 1 - Div1 medium] (14649) | 5 | |

132 | Spy Syndrome 2 | Codeforces | Manthan, Codefest 16 | 5 | |

133 | Famil Door and Brackets | Codeforces | Codeforces Round #343 (Div. 2) | 5 | |

134 | Running Track | Codeforces | Codeforces Round #338 (Div. 2) | 5 | |

135 | New Year and Ancient Prophecy | Codeforces | Good Bye 2015 | 5 | |

136 | A Simple Task | Codeforces | Codeforces Round #312 (Div. 2) | 5 | |

137 | Correcting Mistakes | Codeforces | VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) | 5 | |

138 | Pretty Song | Codeforces | Codeforces Round #289 (Div. 2, ACM ICPC Rules) | 5 | |

139 | Obsessive String | Codeforces | Codeforces Round #282 (Div. 1) & Codeforces Round #282 (Div. 2) | 5 | |

140 | Lucky Common Subsequence | Codeforces | Codeforces Round #201 (Div. 1) & Codeforces Round #201 (Div. 2) | 5 | |

141 | Alyona and Strings | Codeforces | Codeforces Round #358 (Div. 2) | 5 | |

142 | Restoring IPv6 | Codeforces | CROC-MBTU 2012, Final Round (Online version, Div. 2) | 6 | |

143 | Two Strings | Codeforces | Codeforces Round #138 (Div. 1) & Codeforces Round #138 (Div. 2) | 6 | |

144 | Wizards and Minimal Spell | Codeforces | Codeforces Round #114 (Div. 2) | 6 | |

145 | Martian Strings | Codeforces | Codeforces Round #106 (Div. 2) | 6 | |

146 | String | Codeforces | Codeforces Beta Round #94 (Div. 1 Only) & Codeforces Beta Round #94 (Div. 2 Only) | 6 | |

147 | Hockey | Codeforces | Codeforces Beta Round #77 (Div. 1 Only) & Codeforces Beta Round #77 (Div. 2 Only) | 6 | |

148 | Beaver | Codeforces | Codeforces Beta Round #71 | 6 | |

149 | Text Messaging | Codeforces | Codeforces Beta Round #64 | 6 | |

150 | Spelling Check | Codeforces | School Team Contest #1 (Winter Computer School 2010/11) | 6 | |

151 | Test | Codeforces | Codeforces Beta Round #25 (Div. 2 Only) | 6 | |

152 | Alphabetic Relation | SPOJ | 6 | ||

153 | Vần hoàn hảo | SPOJ Vietnam | 6 | ||

154 | Do the Untwist | Live Archive | 1998 | North America - Mid-Central USA | 6 |

155 | Unique Strings | SPOJ | 6 | ||

156 | Substitutes in Number | Codeforces | Codeforces Round #265 (Div. 1) & Codeforces Round #265 (Div. 2) | 6 | |

157 | Making Genome in Berland | Codeforces | VK Cup 2016 - Qualification Round 2 | 6 | |

158 | Messenger | Codeforces | Codeforces Round #344 (Div. 2) | 6 | |

159 | Kefa and Watch | Codeforces | Codeforces Round #321 (Div. 2) | 6 | |

160 | Work Group | Codeforces | VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) | 6 | |

161 | Om Nom and Necklace | Codeforces | ZeptoLab Code Rush 2015 | 6 | |

162 | Dreamoon and Strings | Codeforces | Codeforces Round #272 (Div. 2) & Codeforces Round #272 (Div. 1) | 6 | |

163 | Fedor and Essay | Codeforces | Codeforces Round #267 (Div. 2) | 6 | |

164 | Match & Catch | Codeforces | Codeforces Round #244 (Div. 2) | 6 | |

165 | Sereja and Periods | Codeforces | Codeforces Round #187 (Div. 1) & Codeforces Round #187 (Div. 2) | 6 | |

166 | Log Stream Analysis | Codeforces | CROC-MBTU 2012, Elimination Round (ACM-ICPC) | 7 | |

167 | Cyclical Quest | Codeforces | Codeforces Round #146 (Div. 1) & Codeforces Round #146 (Div. 2) | 7 | |

168 | Vasya and Types | Codeforces | Codeforces Beta Round #73 (Div. 1 Only) & Codeforces Beta Round #73 (Div. 2 Only) | 7 | |

169 | Logging | Codeforces | Codeforces Beta Round #16 (Div. 2 Only) | 7 | |

170 | Intellectual Inquiry | Codeforces | CROC 2016 - Elimination Round | 7 | |

171 | Hostname Aliases | Codeforces | CROC 2016 - Qualification | 7 | |

172 | Marbles | Codeforces | Codeforces Round #336 (Div. 1) & Codeforces Round #336 (Div. 2) | 7 | |

173 | Ann and Half-Palindrome | Codeforces | Codeforces Round #311 (Div. 2) | 7 | |

174 | Encoding | Codeforces | VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) | 7 | |

175 | Good Substrings | Codeforces | ABBYY Cup 3.0 | 7 | |

176 | Tree-String Problem | Codeforces | Croc Champ 2013 - Qualification Round | 7 | |

177 | Vladik and chat | Codeforces | Codeforces Round #390 (Div. 2) | 7 | |

178 | String Mark | Codeforces | Codeforces Round #448 (Div. 2) | 7 | |

179 | e-Government | Codeforces | VK Cup 2012 Round 2 | 8 | |

180 | Gnikool Ssalg | Codeforces | Unknown Language Round #4 | 8 | |

181 | Calendar | Codeforces | Codeforces Beta Round #54 (Div. 2) | 8 | |

182 | Tricky and Clever Password | Codeforces | Codeforces Beta Round #30 (Codeforces format) | 8 | |

183 | Palisection | Codeforces | Codeforces Beta Round #17 | 8 | |

184 | Three strings | Codeforces | MemSQL Start[c]UP 2.0 - Round 1 | 8 | |

185 | Alphabet Permutations | Codeforces | Codeforces Round #337 (Div. 2) | 8 | |

186 | Matching Names | Codeforces | VK Cup 2015 - Finals, online mirror | 8 | |

187 | Mike and Friends | Codeforces | Codeforces Round #305 (Div. 1) | 8 | |

188 | DZY Loves Strings | Codeforces | Codeforces Round #254 (Div. 1) | 8 | |

189 | Two Permutations | Codeforces | Codeforces Round #131 (Div. 1) | 8 | |

190 | Name | Codeforces | Codeforces Round #116 (Div. 2, ACM-ICPC Rules) | 8 | |

191 | The Next Good String | Codeforces | Codeforces Round #124 (Div. 1) | 9 | |

192 | String Transformation | Codeforces | Codeforces Beta Round #90 | 9 | |

193 | World of Mouth | Codeforces | Unknown Language Round #3 | 9 | |

194 | Smart Boy | Codeforces | School Personal Contest #1 (Winter Computer School 2010/11) - Codeforces Beta Round #38 (ACM-ICPC Rules) | 9 | |

195 | Expensive Strings | Codeforces | Educational Codeforces Round 5 | 9 | |

196 | Birthday | Codeforces | Codeforces Round #327 (Div. 1) | 9 | |

197 | And Yet Another Bracket Sequence | Codeforces | VK Cup 2015 - Round 1 | 9 | |

198 | Dreamoon and Binary | Codeforces | Codeforces Round #272 (Div. 1) | 9 | |

199 | Xenia and String Problem | Codeforces | Codeforces Round #207 (Div. 1) | 9 | |

200 | Have You Ever Heard About the Word? | Codeforces | Codeforces Round #189 (Div. 1) | 9 | |

201 | Representative Sampling | Codeforces | ABBYY Cup 2.0 - Hard | 9 | |

202 | Cool Slogans | Codeforces | Codeforces Round #364 (Div. 1) | 9 | |

203 | Ali goes shopping | Codeforces | Unknown Language Round #2 | 10 | |

204 | Mutation | Codeforces | All-Ukrainian School Olympiad in Informatics | 10 | |

205 | #dynamic-programming (168)</span> | SPOJ | 10 | ||

206 | Pattern Matching | Live Archive | 2004 | Asia - Manila | 10 |

207 | Puzzle Lover | Codeforces | Codeforces Round #339 (Div. 1) | 10 | |

208 | Cutting the Line | Codeforces | Codeforces Round #330 (Div. 1) | 10 | |

209 | Duff is Mad | Codeforces | Codeforces Round #326 (Div. 1) | 10 | |

210 | Digits of Number Pi | Codeforces | Codeforces Round #325 (Div. 1) | 10 | |

211 | Suffix Subgroup | Codeforces | Friday the 13th, Programmers Day | 10 | |

212 | Fibonacci Strings | Codeforces | ABBYY Cup 2.0 - Easy | 10 | |

213 | Fibonacci Strings | Codeforces | ABBYY Cup 2.0 - Easy | 10 | |

214 | Hongcow Masters the Cyclic Shift | Codeforces | Codeforces Round #385 (Div. 1) | 10 | |

215 | Rap God | Codeforces | Codeforces Round #406 (Div. 1) | 10 | |

216 | Wire Crossing | UVA | 10 |