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4491 How many trees? combinatorics divide and conquer dp Statement D Codeforces Beta Round 9 (Div. 2 Only) {9} PROGRAMMING Codeforces Beta Round #9 tutorial 2000
673 Triangles combinatorics dp Statement E Codeforces Beta Round 15 {15} PROGRAMMING Codeforces Beta #15 Tutorial (Incomplete) 2600
1009 Parquet combinatorics constructive algorithms Statement C Codeforces Beta Round 26 (Codeforces format) {26} PROGRAMMING Разбор Codeforces Beta Round #26 (ещё один) 2200
928 Tickets combinatorics math probabilities Statement D Codeforces Beta Round 26 (Codeforces format) {26} PROGRAMMING Разбор Codeforces Beta Round #26 (ещё один) 2800
1271 Bath Queue combinatorics dp probabilities Statement C Codeforces Beta Round 28 (Codeforces format) {28} PROGRAMMING Codeforces Beta Round #28 (Разбор задач A и B) 2700
513 Lesson Timetable combinatorics dp math Statement D Codeforces Beta Round 37 {37} PROGRAMMING Codeforces Beta Round #37 (Tutorial) 2300
809 Number Table combinatorics Statement E Codeforces Beta Round 39 {40} PROGRAMMING Codeforces Beta Round #39 (Разбор задач) 2500
230 Toys brute force combinatorics Statement I School Team Contest 2 (Winter Computer School 2010/11) {44} PROGRAMMING School Team Contest #2 (Winter Computer School 2010/2011): tutorial of A-E, H, J. 2400
453 Pentagon combinatorics graphs matrices Statement E Codeforces Beta Round 48 {51} PROGRAMMING 2300
2400 Right Triangles combinatorics Statement B Codeforces Testing Round 1 {52} PROGRAMMING 1600
3943 Array combinatorics math Statement C Codeforces Beta Round 53 {57} PROGRAMMING Codeforces Beta Round #53 [Analysis] 1900
135534 Ultra-Fast Mathematician implementation Statement A Codeforces Beta Round 57 (Div. 2) {61} PROGRAMMING Round 57-A 900
1008 Ski Base combinatorics dsu graphs Statement C Codeforces Beta Round 75 (Div. 1 Only) {91} PROGRAMMING Analysis Codeforces Beta Round #75 2500
4243 Basketball Team combinatorics dp math probabilities Statement B Codeforces Beta Round 83 (Div. 1 Only) {107} PROGRAMMING Tutorial 1700
900 Petya and Coloring combinatorics dp Statement D Codeforces Beta Round 85 (Div. 1 Only) {111} PROGRAMMING Codeforces Beta Round #85: Разбор задач 2300
142 Sleeping combinatorics implementation math Statement E Codeforces Beta Round 86 (Div. 1 Only) {113} PROGRAMMING Codeforces Beta Round #86 Editorial 2600
1432 Lucky Permutation brute force combinatorics number theory Statement C Codeforces Beta Round 91 (Div. 1 Only) {121} PROGRAMMING Разбор задач 2000
720 Brackets combinatorics dp greedy Statement C Codeforces Beta Round 92 (Div. 1 Only) {123} PROGRAMMING Codeforces Beta Round #92 - Analysis 2300
4844 Permutations brute force combinatorics implementation Statement B Codeforces Beta Round 92 (Div. 2 Only) {124} PROGRAMMING Codeforces Beta Round #92 - Analysis 1400
3238 Games with Rectangle combinatorics dp Statement C Codeforces Beta Round 94 (Div. 1 Only) {128} PROGRAMMING 3219 2100
12538 The World is a Theatre combinatorics math Statement C Codeforces Beta Round 95 (Div. 2) {131} PROGRAMMING Разбор Codeforces Beta Round #95 (Div.2) 1500
356 Weak Subsequence combinatorics Statement E Codeforces Beta Round 97 (Div. 1) {135} PROGRAMMING Codeforces Beta Round #97: editorial 2800
1035 New Year Garland combinatorics dp Statement E Codeforces Round 100 {140} PROGRAMMING Codeforces Round #100: problem analysis 2600
2144 Lucky Subsequence combinatorics dp math Statement C Codeforces Round 104 (Div. 1) {145} PROGRAMMING Codeforces Round #104 - Editorial 2200
269 Lucky Pair combinatorics data structures implementation Statement D Codeforces Round 104 (Div. 1) {145} PROGRAMMING Codeforces Round #104 - Editorial 2800
5292 Quantity of Strings combinatorics dfs and similar graphs math Statement B Codeforces Round 107 (Div. 1) {150} PROGRAMMING Tutorial 1800
11616 Pocket Book combinatorics Statement C Codeforces Round 108 (Div. 2) {152} PROGRAMMING Разбор задач Codeforces Round #108 (Div. 2) 1500
2619 Cipher combinatorics dp Statement C Codeforces Round 110 (Div. 1) {156} PROGRAMMING Codeforces Round 110 — Разбор задач 2100
2026 Clues combinatorics graphs Statement D Codeforces Round 110 (Div. 1) {156} PROGRAMMING Codeforces Round 110 — Разбор задач 2400
4743 Star *special combinatorics Statement B April Fools Day Contest {171} PROGRAMMING April Fools Day Contest: editorial 1300
528 Playing with Superglue combinatorics constructive algorithms Statement C Croc Champ 2012 - Round 2 {176} PROGRAMMING Croc Champ 2012 — Round 2 — Editorial 2000
483 Thoroughly Bureaucratic Organization binary search combinatorics Statement E Codeforces Round 127 (Div. 1) {201} PROGRAMMING 2600
6572 Little Elephant and Interval binary search combinatorics dp Statement A Codeforces Round 129 (Div. 1) {204} PROGRAMMING Tutorial 1600
483 Cowboys combinatorics dp math Statement C VK Cup 2012 Finals (unofficial online-version) {212} PROGRAMMING 2200
1977 Numbers combinatorics dp Statement B Codeforces Round 131 (Div. 1) {213} PROGRAMMING Codeforces Round #131 Tutorial 2200
671 Periodical Numbers combinatorics dp number theory Statement E Codeforces Round 132 (Div. 2) {215} PROGRAMMING Codeforces Round #132 (Div. 2) Tutorial 2600
273 Bitonix' Patrol bitmasks brute force combinatorics dfs and similar math Statement D Codeforces Round 134 (Div. 1) {217} PROGRAMMING Editorial for Codeforces Round #134 2800
1750 Partial Sums combinatorics math number theory Statement C Codeforces Round 138 (Div. 1) {223} PROGRAMMING Tutorial 2200
1778 Triangles combinatorics graphs math Statement C Codeforces Round 142 (Div. 1) {229} PROGRAMMING Codeforces Round #142 Problem Analysis 2100
524 Gifts combinatorics dp math probabilities Statement E Codeforces Round 142 (Div. 1) {229} PROGRAMMING Codeforces Round #142 Problem Analysis 2500
1651 Table bitmasks combinatorics dp math Statement B Codeforces Round 144 (Div. 1) {232} PROGRAMMING Editorial for Codeforces Round #144 2200
884 Number Challenge combinatorics dp implementation math number theory Statement E Codeforces Round 146 (Div. 1) {235} PROGRAMMING Codeforces Round #146 Tutorial 2600
21079 Points on Line binary search combinatorics two pointers Statement A Codeforces Round 153 (Div. 1) {251} PROGRAMMING Editorial of Codeforces Round #153 1400
1599 Little Elephant and Elections brute force combinatorics dp Statement B Codeforces Round 157 (Div. 1) {258} PROGRAMMING Codeforces Round #157 — Editorial 2100
1951 Little Elephant and LCM binary search combinatorics dp math Statement C Codeforces Round 157 (Div. 1) {258} PROGRAMMING Codeforces Round #157 — Editorial 2400
2828 Dima and Two Sequences combinatorics math sortings Statement D Codeforces Round 167 (Div. 2) {272} PROGRAMMING Codeforces Round #167 tutorial 1800
1294 Dima and Horses combinatorics constructive algorithms graphs Statement E Codeforces Round 167 (Div. 2) {272} PROGRAMMING Codeforces Round #167 tutorial 2300
853 Cow Tennis Tournament combinatorics data structures math Statement E Codeforces Round 174 (Div. 1) {283} PROGRAMMING Math Problems on Codeforces #174 2700
1671 Permutation Sum bitmasks combinatorics dp implementation meet-in-the-middle Statement D Codeforces Round 175 (Div. 2) {285} PROGRAMMING Codeforces Round #175 (Div. 2) Tutorial 1900
1290 Positions in Permutations combinatorics dp math Statement E Codeforces Round 175 (Div. 2) {285} PROGRAMMING Codeforces Round #175 (Div. 2) Tutorial 2600
3203 Polo the Penguin and Houses combinatorics Statement B Codeforces Round 177 (Div. 1) {288} PROGRAMMING Tutorial 1700
837 Polo the Penguin and Trees combinatorics dfs and similar trees Statement D Codeforces Round 177 (Div. 1) {288} PROGRAMMING Codeforces Round #177, editorial 2300
940 Distinct Paths brute force combinatorics Statement B Croc Champ 2013 - Round 2 {293} PROGRAMMING Croc Champ 2013 — Round 2 — Editorial 2600
4312 Shaass and Lights combinatorics number theory Statement C Codeforces Round 178 (Div. 2) {294} PROGRAMMING Codeforces Round #178 Editorial 1900
738 Greg and Caves combinatorics dp Statement D Codeforces Round 179 (Div. 1) {295} PROGRAMMING Codeforces Round #179 tutorial 2400
1933 Greg and Friends combinatorics dp graphs shortest paths Statement C Codeforces Round 179 (Div. 1) {295} PROGRAMMING Codeforces Round #179 tutorial 2500
2667 Yaroslav and Two Strings combinatorics dp Statement B Codeforces Round 179 (Div. 2) {296} PROGRAMMING Codeforces Round #179 tutorial 2000
11600 Beautiful Numbers brute force combinatorics Statement C Codeforces Round 181 (Div. 2) {300} PROGRAMMING English Tutorial 1800
555 Olya and Graph combinatorics math Statement D Codeforces Round 184 (Div. 2) {305} PROGRAMMING 7712 2600
619 White, Black and White Again combinatorics number theory Statement C Testing Round 6 {306} PROGRAMMING 2200
3019 Malek Dance Club combinatorics math Statement A Codeforces Round 189 (Div. 1) {319} PROGRAMMING Codeforces Round #189 — Editorial 1700
13152 Ciel and Flowers combinatorics math Statement B Codeforces Round 190 (Div. 2) {322} PROGRAMMING Codeforces Round #190 — Editorial 1600
963 Black-and-White Cube combinatorics constructive algorithms Statement A Testing Round 7 {323} PROGRAMMING 1600
940 The Red Button combinatorics dfs and similar dsu graphs greedy Statement E MemSQL start[c]up Round 1 {325} PROGRAMMING Editorial 2700
3659 Magic Five combinatorics math Statement C Codeforces Round 191 (Div. 2) {327} PROGRAMMING Codeforces Round #191 — Tutorial 1700
1575 Axis Walking bitmasks combinatorics constructive algorithms dp meet-in-the-middle Statement E Codeforces Round 191 (Div. 2) {327} PROGRAMMING Codeforces Round #191 — Tutorial 2500
1212 Vasily the Bear and Beautiful Strings combinatorics math number theory Statement D Codeforces Round 195 (Div. 2) {336} PROGRAMMING Tutorial Codeforces Round #195 (Div. 2) 2400
126 Vasily the Bear and Painting Square bitmasks combinatorics dp implementation Statement E Codeforces Round 195 (Div. 2) {336} PROGRAMMING Tutorial Codeforces Round #195 (Div. 2) 2600
4668 Tourist Problem combinatorics implementation math Statement C Codeforces Round 198 (Div. 2) {340} PROGRAMMING Tutorial 1700
2742 Iahub and Permutations combinatorics math Statement E Codeforces Round 198 (Div. 2) {340} PROGRAMMING Tutorial 2200
2721 Jeff and Furik combinatorics dp probabilities Statement B Codeforces Round 204 (Div. 1) {351} PROGRAMMING Codeforces Round #204 — tutorial 2100
2430 Two Heaps combinatorics constructive algorithms greedy implementation math sortings Statement B Codeforces Round 205 (Div. 2) {353} PROGRAMMING 9145 1800
1395 Compartments combinatorics constructive algorithms greedy implementation Statement C Codeforces Round 207 (Div. 1) {356} PROGRAMMING Codeforces Round #207: разбор задач 2200
1212 Levko and Strings combinatorics dp Statement C Codeforces Round 210 (Div. 1) {360} PROGRAMMING Codeforces Round #210 editorial 2700
4948 Matrix combinatorics data structures implementation Statement A Codeforces Round 213 (Div. 1) {364} PROGRAMMING Codeforces Round #213 Editorial 1800
1387 Sereja and Intervals combinatorics dp Statement E Codeforces Round 215 (Div. 1) {367} PROGRAMMING Codeforces Round #215 — tutorial 2600
189 Drawing Circles is Fun combinatorics geometry Statement E Codeforces Round 219 (Div. 1) {372} PROGRAMMING 9944 2900
3485 Inna and Nine combinatorics greedy Statement B Codeforces Round 220 (Div. 2) {374} PROGRAMMING Codeforces Round #220 (Div. 2) разбор 1600
521 Sereja and Cinema combinatorics math Statement D Codeforces Round 223 (Div. 1) {380} PROGRAMMING Codeforces Round #223 — Tutorial 2500
430 Ksenia and Combinatorics combinatorics dp Statement E Codeforces Round 224 (Div. 2) {382} PROGRAMMING Codeforces Round #224 (Div. 2) Editorial 2600
4281 Vowels combinatorics divide and conquer dp Statement E Codeforces Round 225 (Div. 1) {383} PROGRAMMING Tutorial 2700
664 Yet Another Number Sequence combinatorics math matrices Statement C Codeforces Round 230 (Div. 1) {392} PROGRAMMING 1500.0 83942
464 On Sum of Number of Inversions in Permutations combinatorics math Statement D Codeforces Round 232 (Div. 1) {396} PROGRAMMING 2000.0 Codeforces Round #232 Editorial (restored)
1626 On Number of Decompositions into Multipliers combinatorics math number theory Statement A Codeforces Round 232 (Div. 1) {396} PROGRAMMING 500.0 Codeforces Round #232 Editorial (restored)
4555 Roman and Numbers bitmasks brute force combinatorics dp number theory Statement D Codeforces Round 235 (Div. 2) {401} PROGRAMMING Codeforces Round #235 (Div. 2) — Tutorial 2000
1231 Beautiful Pairs of Numbers combinatorics dp Statement D Codeforces Round 236 (Div. 1) {403} PROGRAMMING Editorial Codeforces Round #236 2200
1189 Curious Array brute force combinatorics implementation math Statement C Codeforces Round 239 (Div. 1) {407} PROGRAMMING Codeforces Round #239 Editorial 2500
29009 Mashmokh and ACM combinatorics dp number theory Statement B Codeforces Round 240 (Div. 1) {414} PROGRAMMING Codeforces Round #240 Editorial 1500
2355 Mashmokh and Reverse Operation combinatorics divide and conquer Statement C Codeforces Round 240 (Div. 1) {414} PROGRAMMING Codeforces Round #240 Editorial 2400
2871 Random Task binary search bitmasks combinatorics dp math Statement D Codeforces Round 247 (Div. 2) {431} PROGRAMMING Editorial Codeforces Round #247 (Div. 2) 2200
2126 The Child and Binary Tree combinatorics divide and conquer fft number theory Statement E Codeforces Round 250 (Div. 1) {438} PROGRAMMING Tutorial 3100
1835 Devu and Birthday Celebration combinatorics dp math Statement E Codeforces Round 251 (Div. 2) {439} PROGRAMMING Codeforces Round #251 Editorial 2600
6101 Jzzhu and Numbers bitmasks combinatorics dp Statement D Codeforces Round 257 (Div. 1) {449} PROGRAMMING Codeforces Round #257 Editorial 2400
4495 Devu and Flowers bitmasks combinatorics number theory Statement E Codeforces Round 258 (Div. 2) {451} PROGRAMMING Codeforces Round #258 Editorial 2400
1748 Magic Trick combinatorics math probabilities Statement C MemSQL Start[c]UP 2.0 - Round 1 {452} PROGRAMMING MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials 2100
388 Bingo! combinatorics math probabilities Statement D MemSQL Start[c]UP 2.0 - Round 2 {457} PROGRAMMING MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials 2700
47322 Pashmak and Flowers combinatorics implementation sortings Statement B Codeforces Round 261 (Div. 2) {459} PROGRAMMING Codeforces Round #261 Editorial 1300
6480 Pashmak and Buses combinatorics constructive algorithms math Statement C Codeforces Round 261 (Div. 2) {459} PROGRAMMING Codeforces Round #261 Editorial 1900
3744 Increase Sequence combinatorics dp Statement D Codeforces Round 266 (Div. 2) {466} PROGRAMMING Editorial Codeforces Round #266 (Div. 2) 2300
36817 Dreamoon and WiFi bitmasks brute force combinatorics dp math probabilities Statement B Codeforces Round 272 (Div. 2) {476} PROGRAMMING 1300
41118 Random Teams combinatorics constructive algorithms greedy math Statement B Codeforces Round 273 (Div. 2) {478} PROGRAMMING Editorial 1300
5604 Riding in a Lift combinatorics dp Statement E Codeforces Round 274 (Div. 2) {479} PROGRAMMING Codeforces Round #274: editorial 2000
590 Random Function and Tree combinatorics dp trees Statement D Codeforces Round 275 (Div. 1) {482} PROGRAMMING Codeforces Round #275 Editorial 2600
7036 Unbearable Controversy of Being brute force combinatorics dfs and similar graphs Statement D Codeforces Round 277.5 (Div. 2) {489} PROGRAMMING Codeforces Round #277.5 (Div. 2) Editorial [A-D for now] 1700
1937 Special Matrices combinatorics dp Statement F Codeforces Round 277.5 (Div. 2) {489} PROGRAMMING Codeforces Round #277.5 (Div. 2) Editorial [A-D for now] 2200
3274 New Year Santa Network combinatorics dfs and similar graphs trees Statement D Good Bye 2014 {500} PROGRAMMING Tutorial 2 1900
951 Misha and Palindrome Degree binary search combinatorics implementation Statement E Codeforces Round 285 (Div. 2) {501} PROGRAMMING Tutorial 2800
916 Mr. Kitayuta's Gift combinatorics dp matrices strings Statement E Codeforces Round 286 (Div. 1) {506} PROGRAMMING Editorial 2900
8129 Ilya and Escalator combinatorics dp math probabilities Statement D Codeforces Round 293 (Div. 2) {518} PROGRAMMING Codeforces Round #293 (Div.2) Editorial 1900
417 Pasha and Pipe binary search brute force combinatorics dp implementation Statement F Codeforces Round 293 (Div. 2) {518} PROGRAMMING Codeforces Round #293 (Div.2) Editorial 2800
2083 Pluses everywhere combinatorics dp math number theory Statement E Codeforces Round 295 (Div. 2) {520} PROGRAMMING Codeforces Round #295 Editorial (now with bonuses!) 2500
25713 Tavas and SaDDas bitmasks brute force combinatorics implementation Statement B Codeforces Round 299 (Div. 2) {535} PROGRAMMING Codeforces Round #299 Editorial 1100
3383 Mike and Foam bitmasks combinatorics dp math number theory Statement C Codeforces Round 305 (Div. 1) {547} PROGRAMMING Codeforces Round #305 Editorial 2700
2097 GukiZ and Binary Operations combinatorics implementation math matrices number theory Statement D Codeforces Round 307 (Div. 2) {551} PROGRAMMING Tutorial 2400
4839 Vanya and Triangles brute force combinatorics data structures geometry math sortings Statement D Codeforces Round 308 (Div. 2) {552} PROGRAMMING Codeforces #308 (Div. 2) Editorial 1900
9790 Kyoya and Colored Balls combinatorics dp math Statement A Codeforces Round 309 (Div. 1) {553} PROGRAMMING Codeforces Round #309 Editorial 1700
2263 Kyoya and Permutation binary search combinatorics constructive algorithms greedy implementation math Statement B Codeforces Round 309 (Div. 1) {553} PROGRAMMING Codeforces Round #309 Editorial 2200
2373 Vitaly and Cycle combinatorics dfs and similar graphs math Statement D Codeforces Round 311 (Div. 2) {557} PROGRAMMING Codeforces Round #311 (Div.2) Editorial 2300
8026 Gerald and Giant Chess combinatorics dp math number theory Statement C Codeforces Round 313 (Div. 1) {559} PROGRAMMING Codeforces Round 313 — Extended editoral 2500
475 Randomizer combinatorics geometry probabilities Statement D Codeforces Round 313 (Div. 1) {559} PROGRAMMING Codeforces Round 313 — Extended editoral 2800
2382 Symmetric and Transitive combinatorics dp math Statement B Codeforces Round 315 (Div. 1) {568} PROGRAMMING Codeforces Round #315 Editorial 2100
2102 Pig and Palindromes combinatorics dp Statement E Codeforces Round 316 (Div. 2) {570} PROGRAMMING Codeforces Round #316 Editorial 2600
2676 Lengthening Sticks combinatorics implementation math Statement A Codeforces Round 317 [AimFund Thanks-Round] (Div. 1) {571} PROGRAMMING Codeforces Round #317 [AimFund Thanks-Round] Editorial 2300
1876 Bots combinatorics number theory Statement H Bubble Cup 8 - Finals [Online Mirror] {575} PROGRAMMING Bubble Cup finals 2015 Results and Editorial 1800
14756 Modulo Sum combinatorics data structures dp two pointers Statement B Codeforces Round 319 (Div. 2) {577} PROGRAMMING Editorial Codeforces Round #319 1800
13638 Kolya and Tanya combinatorics Statement B Codeforces Round 324 (Div. 2) {584} PROGRAMMING Tutorial 1500
1220 Present for Vitalik the Philatelist combinatorics math number theory Statement E Codeforces Round 325 (Div. 1) {585} PROGRAMMING Разбор Codeforces Round #325 2800
2330 Wilbur and Points combinatorics greedy sortings Statement C Codeforces Round 331 (Div. 2) {596} PROGRAMMING Codeforces Round #331 Editorial 1700
2708 Moodular Arithmetic combinatorics dfs and similar dsu math number theory Statement B Codeforces Round 334 (Div. 1) {603} PROGRAMMING Codeforces Round #334 Editorial 2000
7449 Hamming Distance Sum combinatorics strings Statement B Codeforces Round 336 (Div. 2) {608} PROGRAMMING Codeforces Round #336 Editorial 1500
27497 Pasha and Stick combinatorics math Statement A Codeforces Round 337 (Div. 2) {610} PROGRAMMING Codeforces Round #337 (Div.2) Editorial 1000
1998 Square Root of Permutation combinatorics constructive algorithms dfs and similar graphs math Statement E Educational Codeforces Round 4 {612} PROGRAMMING 22299 2200
19959 Chocolate combinatorics Statement B Codeforces Round 340 (Div. 2) {617} PROGRAMMING Tutorial 1300
11599 Wet Shark and Bishops combinatorics implementation Statement B Codeforces Round 341 (Div. 2) {621} PROGRAMMING Editorial 1300
6218 Wet Shark and Flowers combinatorics math number theory probabilities Statement C Codeforces Round 341 (Div. 2) {621} PROGRAMMING 1700
611 Transforming Sequence combinatorics dp fft math Statement E AIM Tech Round (Div. 1) {623} PROGRAMMING AIM Tech Round Tutorial 3300
3146 Jerry's Protest brute force combinatorics dp probabilities Statement D 8VC Venture Cup 2016 - Elimination Round {626} PROGRAMMING 23522 1800
1148 Famil Door and Roads combinatorics data structures dfs and similar dp probabilities trees Statement E Codeforces Round 343 (Div. 2) {629} PROGRAMMING Editorial of Codeforces Round #343 (Div.2) 2400
14829 Far Relative’s Birthday Cake brute force combinatorics constructive algorithms implementation Statement A Codeforces Round 343 (Div. 2) {629} PROGRAMMING Editorial of Codeforces Round #343 (Div.2) 800
26806 Lucky Numbers combinatorics math Statement C Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING 24160 1100
8040 Selection of Personnel combinatorics math Statement F Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1500
5655 Benches combinatorics math Statement H Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING 24160 1700
3297 Challenge Pennants combinatorics math Statement G Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1800
8233 Parking Lot combinatorics math Statement I Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1900
966 Cowslip Collections combinatorics math number theory Statement F CROC 2016 - Elimination Round {645} PROGRAMMING Editorial for CROC 2016 Elimination Round 2500
3749 Foe Pairs combinatorics sortings two pointers Statement C Educational Codeforces Round 10 {652} PROGRAMMING Editorial of Educational Codeforces Round 10 1800
642 Move by Prime combinatorics math number theory Statement G IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} PROGRAMMING IndiaHacks Finals 2016 — Editorial 3000
1315 Fence Divercity combinatorics dp number theory Statement G Codeforces Round 346 (Div. 2) {659} PROGRAMMING Editorial for Codeforces Round #346 (Div. 2) 2500
1954 Different Subsets For All Tuples combinatorics Statement E Educational Codeforces Round 11 {660} PROGRAMMING Editorial of Educational Codeforces Round 11 2300
910 Codeword combinatorics strings Statement C Codeforces Round 349 (Div. 1) {666} PROGRAMMING Codeforces Round #349 Editorial 2400
6942 Vanya and Label bitmasks combinatorics implementation strings Statement C Codeforces Round 355 (Div. 2) {677} PROGRAMMING Codeforces Round #355 (Div. 2) Editorial 1500
4493 Robbers' watch brute force combinatorics dp math Statement A Codeforces Round 359 (Div. 1) {685} PROGRAMMING Codeforces Round #359 Editorial 1700
6161 Mike and Chocolate Thieves binary search combinatorics math Statement C Codeforces Round 361 (Div. 2) {689} PROGRAMMING 45912 1700
2118 Mike and Geometry Problem combinatorics data structures dp geometry implementation Statement E Codeforces Round 361 (Div. 2) {689} PROGRAMMING Tutorial 2300
1459 The Wall (medium) combinatorics Statement D2 Helvetic Coding Contest 2016 online mirror (teams, unrated) {690} PROGRAMMING Tutotial 1800
2212 PLEASE combinatorics dp implementation math matrices Statement C Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 2200
487 Coprime Permutation combinatorics number theory Statement F Codeforces Round 363 (Div. 1) {698} PROGRAMMING Solution 3000
4954 Directed Roads combinatorics dfs and similar graphs math Statement D Codeforces Round 369 (Div. 2) {711} PROGRAMMING 46830 1900
1991 Memory and Scores combinatorics dp math Statement D Codeforces Round 370 (Div. 2) {712} PROGRAMMING Codeforces Round #370 Editorial 2100
451 Complete the Permutations combinatorics fft graphs math Statement E Codeforces Round 372 (Div. 1) {715} PROGRAMMING Codeforces Round #372 Editorial 3400
1078 Research Rover combinatorics dp Statement E Intel Code Challenge Elimination Round (Div. 1 + Div. 2, combined) {722} PROGRAMMING Tutorial 2800
520 Uniformly Branched Trees combinatorics dp trees Statement F Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} PROGRAMMING Tutorial 2800
7958 Tennis Championship combinatorics constructive algorithms greedy math Statement C Codeforces Round 382 (Div. 2) {735} PROGRAMMING Codeforces Round #382 Editorial 1700
541 Permutations math matrices Statement D Codeforces Round 382 (Div. 1) {736} PROGRAMMING 48659 2700
481 Igor and Interesting Numbers brute force combinatorics dp math Statement F Codeforces Round 387 (Div. 2) {747} PROGRAMMING 49171 2600
525 New Year and Binary Tree Paths bitmasks brute force combinatorics dp Statement G Good Bye 2016 {750} PROGRAMMING Good Bye 2016 — hints and codes 3100
1022 PolandBall and Many Other Balls combinatorics divide and conquer dp fft math number theory Statement G 8VC Venture Cup 2017 - Elimination Round {755} PROGRAMMING 8VC Venture Cup 2017 — Elimination Round [Editorial] 3100
1081 Bacterial Melee brute force combinatorics dp string suffix structures Statement D 8VC Venture Cup 2017 - Final Round {756} PROGRAMMING 8VC Venture Cup 2017 — Final Round and Codeforces Round #393 Editorial 2500
205 Byteland coins combinatorics dp math Statement E 8VC Venture Cup 2017 - Final Round {756} PROGRAMMING 8VC Venture Cup 2017 — Final Round and Codeforces Round #393 Editorial 3200
1543 Bash Plays with Functions brute force combinatorics dp number theory Statement E Codecraft-17 and Codeforces Round 391 (Div. 1 + Div. 2, combined) {757} PROGRAMMING CodeCraft-17 and Codeforces Round #391 (Div. 1 + Div. 2, combined) Editorial 2400
478 Tree nesting combinatorics graphs trees Statement F Educational Codeforces Round 17 {762} PROGRAMMING Tutorial 2900
1121 Barrels and boxes brute force combinatorics math number theory probabilities Statement F Divide by Zero 2017 and Codeforces Round 399 (Div. 1 + Div. 2, combined) {768} PROGRAMMING Editorial Divide by Zero and Codeforces Round #399 (Div. 1+2, combined) 2300
218 Test Data Generation combinatorics divide and conquer dp fft math number theory Statement F VK Cup 2017 - Round 3 {773} PROGRAMMING VK Cup 2017 Round 3 + Codeforces Round #412 -- Tutorial 3400
367 Sherlock and the Encrypted Data bitmasks combinatorics dp Statement G ICM Technex 2017 and Codeforces Round 400 (Div. 1 + Div. 2, combined) {776} PROGRAMMING ICM Technex 2017 and Codeforces Round #400 (Div. 1 + Div. 2, combined) Editorial 2800
3656 Anton and School - 2 combinatorics dp math number theory Statement D Codeforces Round 404 (Div. 2) {785} PROGRAMMING Editorial 2200
2882 Weird journey combinatorics constructive algorithms dfs and similar dsu graphs Statement B Codeforces Round 407 (Div. 1) {788} PROGRAMMING Codeforces Round #407(Div.1 + Div.2) Editorial 2200
401 Replace All combinatorics dp math Statement G Tinkoff Challenge - Final Round (Codeforces Round 414, rated, Div. 1 + Div. 2) {794} PROGRAMMING 3400
4600 Coprime Subsequences bitmasks combinatorics number theory Statement F Educational Codeforces Round 20 {803} PROGRAMMING 51768 2100
10151 Minimum number of steps combinatorics greedy implementation math Statement B Codeforces Round 411 (Div. 1) {804} PROGRAMMING Codeforces Round #411 Editorial 1400
215 Fake bullions combinatorics dfs and similar dp graphs number theory Statement F Codeforces Round 411 (Div. 1) {804} PROGRAMMING Codeforces Round #411 Editorial 3400
905 Find a car combinatorics divide and conquer dp Statement C Codeforces Round 415 (Div. 1) {809} PROGRAMMING 52099 2900
725 An unavoidable detour for home combinatorics dp graphs shortest paths Statement E Codeforces Round 418 (Div. 2) {814} PROGRAMMING Codeforces Round #418 (Div. 2) Editorial 2700
1600 Karen and Test brute force combinatorics constructive algorithms math Statement B Codeforces Round 419 (Div. 1) {815} PROGRAMMING Codeforces Round #419 Editorial 2200
749 Karen and Cards binary search combinatorics data structures geometry Statement D Codeforces Round 419 (Div. 1) {815} PROGRAMMING Codeforces Round #419 Editorial 2700
6420 Makes And The Product combinatorics implementation math sortings Statement B Educational Codeforces Round 23 {817} PROGRAMMING 52638 1500
977 Singer House combinatorics dp graphs trees Statement D Codeforces Round 424 (Div. 1, rated, based on VK Cup Finals) {830} PROGRAMMING Codeforces Round #424 Editorial 2800
507 Ever-Hungry Krakozyabra brute force combinatorics greedy math Statement C Codeforces Round 426 (Div. 1) {833} PROGRAMMING Codeforces Round #426 Editorial 2600
1078 Prefix Sums binary search brute force combinatorics math matrices Statement F Educational Codeforces Round 26 {837} PROGRAMMING 53662 2500
3541 Winter is here combinatorics dp math number theory Statement D Codeforces Round 428 (Div. 2) {839} PROGRAMMING Codeforces Round #428 editorial 2200
7445 Leha and Function combinatorics greedy math number theory sortings Statement A Codeforces Round 429 (Div. 1) {840} PROGRAMMING Editorial 1300
2064 On the Bench combinatorics dp Statement C Codeforces Round 429 (Div. 1) {840} PROGRAMMING Editorial 2600
9025 Rectangles combinatorics math Statement B AIM Tech Round 4 (Div. 2) {844} PROGRAMMING AIM Tech Round 4 -- Editorial 1300
455 Shake It! combinatorics dp flows graphs Statement D Codeforces Round 431 (Div. 1) {848} PROGRAMMING Codeforces Round #431 Editorial 2900
242 Days of Floral Colours combinatorics divide and conquer dp fft math Statement E Codeforces Round 431 (Div. 1) {848} PROGRAMMING Codeforces Round #431 Editorial 3400
652 Product transformation combinatorics math number theory Statement F Bubble Cup X - Finals [Online Mirror] {852} PROGRAMMING Tutorial 2300
721 Eleventh Birthday combinatorics dp math Statement C Russian Code Cup 2017 - Finals [Unofficial Mirror, Div. 1 Only Recommended, Teams Allowed] {856} PROGRAMMING Tutorial 2400
2111 Desk Disorder combinatorics dfs and similar dsu graphs trees Statement E MemSQL Start[c]UP 3.0 - Round 1 {859} PROGRAMMING Tutorial 2100
163 Flowers and Chocolate combinatorics math matrices Statement G MemSQL Start[c]UP 3.0 - Round 2 (onsite finalists) {865} PROGRAMMING MemSQL Start[c]UP 3.0 Round 2 Editorial 3200
5188 The Intriguing Obsession combinatorics dp math Statement C Codeforces Round 439 (Div. 2) {869} PROGRAMMING Tutorial 1800
2483 High Cry binary search bitmasks combinatorics data structures divide and conquer Statement D Codeforces Round 441 (Div. 1, by Moscow Team Olympiad) {875} PROGRAMMING Codeforces Round #441. Editorial. 2200
735 Numbers on the blackboard combinatorics dp Statement E Codeforces Round 443 (Div. 1) {878} PROGRAMMING Editorial 3200
1210 Maximum Element combinatorics dp math Statement E Технокубок 2018 - Отборочный Раунд 3 {886} PROGRAMMING Editorial Codeforces Round 445 (and Technocup 2018 — Elimination Round 3) 2500
10454 Almost Identity Permutations combinatorics dp math Statement D Educational Codeforces Round 32 {888} PROGRAMMING Educational Codeforces Round 32 - Editorial 1600
1109 Lust combinatorics math matrices Statement E Codeforces Round 446 (Div. 1) {891} PROGRAMMING Codeforces Round #446 Editorial 2800
4186 Counting Arrays combinatorics dp math number theory Statement E Educational Codeforces Round 33 (Rated for Div. 2) {893} PROGRAMMING 55989 2000
4692 Ralph And His Magic Field combinatorics constructive algorithms math number theory Statement B Codeforces Round 447 (Div. 2) {894} PROGRAMMING Codeforces Round #447 (Div.2 Only) Editorial 1800
7300 Square Subsets bitmasks combinatorics dp math Statement C Codeforces Round 448 (Div. 2) {895} PROGRAMMING Codeforces Round #448(Div.2) Editorial 2000
1234 String Mark combinatorics math strings Statement D Codeforces Round 448 (Div. 2) {895} PROGRAMMING Codeforces Round #448(Div.2) Editorial 2300
609 Nephren Runs a Cinema chinese remainder theorem combinatorics math number theory Statement D Codeforces Round 449 (Div. 1) {896} PROGRAMMING Codeforces Round #449 Editorial 2800
3771 Unusual Sequences bitmasks combinatorics dp math number theory Statement D Codeforces Round 450 (Div. 2) {900} PROGRAMMING Codeforces Round #450(Div. 2). Editorial. 2100
836 New Year and Entity Enumeration bitmasks combinatorics dp math Statement E Good Bye 2017 {908} PROGRAMMING Good Bye 2017 Editorial 2400
4201 Travelling Salesman and Special Numbers brute force combinatorics dp Statement C Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} PROGRAMMING Tutorial 1800
277 Ember and Storm's Tree Game combinatorics dp games trees Statement H Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} PROGRAMMING Tutorial 2900
449 Pollywog combinatorics dp matrices Statement C Codeforces Round 459 (Div. 1) {917} PROGRAMMING Codeforces Round #459 Editorial 2800
1980 List Of Integers binary search bitmasks brute force combinatorics math number theory Statement G Educational Codeforces Round 37 (Rated for Div. 2) {920} PROGRAMMING T 2300
1203 Красивая команда *special combinatorics math Statement C VK Cup 2018 - Квалификация 2 {929} PROGRAMMING Разбор VK Cup 2018 — Квалификация 2 2000
3422 Team Work combinatorics dp math Statement E ICM Technex 2018 and Codeforces Round 463 (Div. 1 + Div. 2, combined) {932} PROGRAMMING 57796 2400
388 A Creative Cutout brute force combinatorics math Statement D Codeforces Round 462 (Div. 1) {933} PROGRAMMING 57763 2900
1536 Max History combinatorics math Statement E Educational Codeforces Round 38 (Rated for Div. 2) {938} PROGRAMMING Educational Codeforces Round 38 — Editorial 2300
640 Fibonacci String Subsequences combinatorics dp matrices Statement F Educational Codeforces Round 39 (Rated for Div. 2) {946} PROGRAMMING 58210 2500
761 Path Counting combinatorics dp Statement H Educational Codeforces Round 40 (Rated for Div. 2) {954} PROGRAMMING 58519 2500
2264 Alternating Tree combinatorics dfs and similar divide and conquer dp probabilities trees Statement E Divide by Zero 2018 and Codeforces Round 474 (Div. 1 + Div. 2, combined) {960} PROGRAMMING Divide by Zero 2018 and Codeforces Round #474 (Div. 1 + Div. 2, combined) Editorial 2200
1201 Bandit Blues combinatorics dp fft math Statement G Divide by Zero 2018 and Codeforces Round 474 (Div. 1 + Div. 2, combined) {960} PROGRAMMING Divide by Zero 2018 and Codeforces Round #474 (Div. 1 + Div. 2, combined) Editorial 2800
1593 Partitions combinatorics math number theory Statement G Educational Codeforces Round 41 (Rated for Div. 2) {961} PROGRAMMING Educational Codeforces Round 41 Editorial 2700
10557 Bus Video System combinatorics math Statement E Codeforces Round 481 (Div. 3) {978} PROGRAMMING T 1400
288 K Paths combinatorics data structures dp fft math Statement H Avito Code Challenge 2018 {981} PROGRAMMING Avito Code Challenge 2018 — разбор 2900
714 Team Players combinatorics Statement G Educational Codeforces Round 44 (Rated for Div. 2) {985} PROGRAMMING Educational Codeforces Round 44 Editorial 2700
5042 Petr and Permutations combinatorics math Statement B Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 1800
3724 Bus Number brute force combinatorics math Statement E Codeforces Round 491 (Div. 2) {991} PROGRAMMING 60181 1800
1603 Cowmpany Cowmpensation combinatorics dp math trees Statement F Codeforces Round 492 (Div. 1) [Thanks, uDebug!] {995} PROGRAMMING Editorial for Codeforces Round #492 [Thanks u-Debug!] 2700
3135 Roman Digits brute force combinatorics dp greedy math Statement B Codeforces Round 493 (Div. 1) {997} PROGRAMMING 60357 2000
2170 Sky Full of Stars combinatorics math Statement C Codeforces Round 493 (Div. 1) {997} PROGRAMMING 60357 2600
514 Cycles in product combinatorics divide and conquer trees Statement D Codeforces Round 493 (Div. 1) {997} PROGRAMMING 60357 2800
5028 Yet Another Problem On a Subsequence combinatorics dp Statement D Educational Codeforces Round 46 (Rated for Div. 2) {1000} PROGRAMMING 60288 1900
13039 Reorder the Array combinatorics data structures math sortings two pointers Statement A Codeforces Round 497 (Div. 1) {1007} PROGRAMMING Editorial for Codeforces Round #497 by Skyglow 1300
1037 Pave the Parallelepiped bitmasks brute force combinatorics math number theory Statement B Codeforces Round 497 (Div. 1) {1007} PROGRAMMING Editorial for Codeforces Round #497 by Skyglow 2400
3317 Intercity Travelling combinatorics math probabilities Statement E Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 1900
2360 Inverse Coloring combinatorics dp math Statement E Educational Codeforces Round 49 (Rated for Div. 2) {1027} PROGRAMMING Educational Codeforces Round 49 Editorial 2100
1821 Order book combinatorics data structures greedy Statement D AIM Tech Round 5 (rated, Div. 1 + Div. 2) {1028} PROGRAMMING 61493 2100
992 Region Separation combinatorics dp number theory trees Statement C Codeforces Round 511 (Div. 1) {1034} PROGRAMMING Codeforces Round #511 Editorial 2900
13225 Classy Numbers combinatorics dp Statement C Educational Codeforces Round 50 (Rated for Div. 2) {1036} PROGRAMMING 61727 1800
1851 Relatively Prime Powers combinatorics math number theory Statement F Educational Codeforces Round 50 (Rated for Div. 2) {1036} PROGRAMMING 61727 2400
1268 Maximum Reduction combinatorics data structures math Statement F Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} PROGRAMMING Tutorial 2400
4757 Mysterious Crime brute force combinatorics math meet-in-the-middle two pointers Statement D Codeforces Round 519 by Botan Investments {1043} PROGRAMMING Codeforces Round #519 Editorial 1700
2981 Make It One bitmasks combinatorics dp math number theory shortest paths Statement F Codeforces Round 519 by Botan Investments {1043} PROGRAMMING Codeforces Round #519 Editorial 2500
787 Shrinking Tree combinatorics dp Statement F Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) {1060} PROGRAMMING User editorial for Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) 2800
1278 Side Transmutations combinatorics strings Statement E Educational Codeforces Round 52 (Rated for Div. 2) {1065} PROGRAMMING Educational Codeforces Round 52 Editorial 2200
3540 Segment Sum bitmasks combinatorics dp math Statement E Educational Codeforces Round 53 (Rated for Div. 2) {1073} PROGRAMMING 62742 2300
8419 Colorful Bricks combinatorics dp math Statement C Avito Cool Challenge 2018 {1081} PROGRAMMING 63888 1600
11559 The Fair Nut and String combinatorics dp implementation Statement C Codeforces Round 526 (Div. 2) {1084} PROGRAMMING 63753 1500