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5462 Line math number theory Statement C Codeforces Beta Round 7 {7} PROGRAMMING 1800
1697 Digital Root number theory Statement C Codeforces Beta Round 10 {10} PROGRAMMING 2000
5405 Monitor binary search number theory Statement C Codeforces Beta Round 16 (Div. 2 Only) {16} PROGRAMMING Codeforces Beta Round #16 Tutorial 1800
21274 Noldbach problem brute force math number theory Statement A Codeforces Beta Round 17 {17} PROGRAMMING Codeforces Beta Round #17 Tutorial 1100
1324 Notepad number theory Statement D Codeforces Beta Round 17 {17} PROGRAMMING Codeforces Beta Round #17 Tutorial 2300
42320 Almost Prime number theory Statement A Codeforces Beta Round 26 (Codeforces format) {26} PROGRAMMING Codeforces Beta Round #26 tutorial 2400
4894 Number With The Given Amount Of Divisors brute force dp number theory Statement E Codeforces Beta Round 27 (Codeforces format, Div. 2) {27} PROGRAMMING Solution of ABC @ Round#27 2100
697 Moon Craters dp sortings Statement C School Team Contest 1 (Winter Computer School 2010/11) {39} PROGRAMMING School Team Contest #1 (Winter Computer School 2010/11): Tutorial 2300
1220 Prime Problem number theory Statement G School Team Contest 3 (Winter Computer School 2010/11) {45} PROGRAMMING 2300
1627 First Digit Law dp math probabilities Statement C Codeforces Beta Round 50 {54} PROGRAMMING Codeforces Beta Round #50: Editorial for problem E 2000
4612 Beautiful numbers dp number theory Statement D Codeforces Beta Round 51 {55} PROGRAMMING Round 51, A 2400
7931 Fortune Telling implementation number theory Statement B Codeforces Beta Round 55 (Div. 2) {59} PROGRAMMING Round 55 (DIV 2) 1200
135534 Ultra-Fast Mathematician implementation Statement A Codeforces Beta Round 57 (Div. 2) {61} PROGRAMMING Round 57-A 900
2011 Harry Potter and Three Spells implementation math Statement A Codeforces Beta Round 60 {65} PROGRAMMING Codeforces Beta Round #60: tutorial 1800
3591 Petya and His Friends constructive algorithms math number theory Statement D Codeforces Beta Round 61 (Div. 2) {66} PROGRAMMING Codeforces Beta Round #61 (Div. 2): Editorial 1700
5353 Irrational problem implementation number theory Statement A Codeforces Beta Round 62 {68} PROGRAMMING Разбор задачи D. CF62 1100
7314 Round Table Knights dp math number theory Statement C Codeforces Beta Round 65 (Div. 2) {71} PROGRAMMING Разбор задач Codeforces Beta Round #65 (Div. 2) 1600
409 Morrowindows math number theory Statement E Codeforces Beta Round 66 {73} PROGRAMMING Codeforces Beta Round #66 editorial: Problems D, E, F 2300
1411 Chessboard Billiard dfs and similar dsu graphs number theory Statement C Codeforces Beta Round 68 {74} PROGRAMMING Solutions for Codeforces Beta Round #68 2100
15528 Modified GCD binary search number theory Statement C Codeforces Beta Round 67 (Div. 2) {75} PROGRAMMING Codeforces Beta Round #67 (Div. 2), my solutions 1600
801 Mice greedy two pointers Statement B All-Ukrainian School Olympiad in Informatics {76} PROGRAMMING All-Ukrainian School Olympiad in Informatics: editorial (A,B,C,D,E,F) 2200
2166 Beaver Game dp games number theory Statement C Codeforces Beta Round 70 (Div. 2) {78} PROGRAMMING Solutions for Codeforces Beta Round #70 (Div. 2) 1900
1032 Numbers dp math number theory Statement D Codeforces Beta Round 72 (Div. 1 Only) {83} PROGRAMMING разбор E 2400
16592 Toy Army math number theory Statement A Codeforces Beta Round 72 (Div. 2 Only) {84} PROGRAMMING 1000
451 Tetris revisited constructive algorithms graph matchings greedy math Statement B Yandex.Algorithm 2011: Round 2 {86} PROGRAMMING Problemset analysis (Yandex, Round 2) 2100
539 Lostborn dp math number theory Statement E Codeforces Beta Round 76 (Div. 1 Only) {93} PROGRAMMING Codeforces Beta Round 76 - задача Е div 1 глазами ее автора. 2600
4097 Petya and Divisors binary search data structures number theory Statement B Codeforces Beta Round 85 (Div. 1 Only) {111} PROGRAMMING Codeforces Beta Round #85: Разбор задач 1900
1440 Double Happiness brute force math number theory Statement C Codeforces Beta Round 86 (Div. 1 Only) {113} PROGRAMMING Codeforces Beta Round #86 Editorial 2200
1742 Very Interesting Game brute force number theory Statement B Codeforces Beta Round 88 {117} PROGRAMMING Неофициальный разбор Codeforces Beta Round #88 1700
1432 Lucky Permutation brute force combinatorics number theory Statement C Codeforces Beta Round 91 (Div. 1 Only) {121} PROGRAMMING Разбор задач 2000
149094 Lucky Division brute force number theory Statement A Codeforces Beta Round 91 (Div. 2 Only) {122} PROGRAMMING BIT solution for Codeforces #91 E 1000
3973 Prime Permutation implementation number theory strings Statement A Codeforces Beta Round 92 (Div. 1 Only) {123} PROGRAMMING Codeforces Beta Round #92 - Analysis 1600
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
2474 Pairs of Numbers brute force dfs and similar math number theory Statement B Codeforces Testing Round 3 {134} PROGRAMMING 1800
8540 Win or Freeze games math number theory Statement A Codeforces Round 107 (Div. 1) {150} PROGRAMMING Tutorial 1600
6101 Colliders math number theory Statement B Codeforces Round 109 (Div. 1) {154} PROGRAMMING Codeforces Round #109: editorial 1700
6484 Ice Sculptures *special brute force number theory Statement D VK Cup 2012 Qualification Round 1 {158} PROGRAMMING Simple solution to vk cup Qualification Round 1 and 2 1900
1481 ucyhf *special brute force implementation number theory Statement F April Fools Day Contest {171} PROGRAMMING April Fools Day Contest: editorial 1700
3144 Pseudorandom Sequence Period *special implementation number theory Statement B Croc Champ 2012 - Qualification Round {172} PROGRAMMING 1800
1509 Calendar Reform *special number theory Statement D Croc Champ 2012 - Qualification Round {172} PROGRAMMING 1900
5094 Rectangular Game number theory Statement B1 ABBYY Cup 2.0 - Easy {177} PROGRAMMING 1000
3348 Rectangular Game number theory Statement B2 ABBYY Cup 2.0 - Easy {177} PROGRAMMING 1200
464 Divisibility Rules math number theory Statement B Codeforces Round 116 (Div. 2, ACM-ICPC Rules) {180} PROGRAMMING 2300
501 Visit of the Great math number theory Statement D Codeforces Round 118 (Div. 1) {185} PROGRAMMING Tutorial 2600
392 Metro Scheme graphs greedy Statement D Codeforces Round 121 (Div. 1) {191} PROGRAMMING Разбор Codeforces Round #121 2800
30225 Hexadecimal's theorem brute force constructive algorithms implementation number theory Statement A Codeforces Round 125 (Div. 2) {199} PROGRAMMING Solutions for Codeforces Round #125 1000
364 Tractor College implementation math number theory ternary search Statement E Codeforces Round 126 (Div. 2) {200} PROGRAMMING Editorial of Codeforces Round #126 (Div. 2) 2200
671 Periodical Numbers combinatorics dp number theory Statement E Codeforces Round 132 (Div. 2) {215} PROGRAMMING Codeforces Round #132 (Div. 2) Tutorial 2600
666 Martian Luck math number theory Statement E Codeforces Round 133 (Div. 2) {216} PROGRAMMING Editorial for Codeforces Round #133 2300
2912 Reducing Fractions implementation math number theory sortings Statement C Codeforces Round 137 (Div. 2) {222} PROGRAMMING Разбор задач Codeforces Round #137 (Div. 2) 2000
1750 Partial Sums combinatorics math number theory Statement C Codeforces Round 138 (Div. 1) {223} PROGRAMMING Tutorial 2200
3391 Well-known Numbers binary search greedy number theory Statement B Codeforces Round 139 (Div. 2) {225} PROGRAMMING 1600
900 Unsolvable math number theory Statement E Codeforces Round 139 (Div. 2) {225} PROGRAMMING Tutorial 2100
1013 Anniversary data structures implementation math matrices number theory Statement C Codeforces Round 140 (Div. 1) {226} PROGRAMMING Codeforces Round #140 Editorial 2100
524 Gifts combinatorics dp math probabilities Statement E Codeforces Round 142 (Div. 1) {229} PROGRAMMING Codeforces Round #142 Problem Analysis 2500
95160 T-primes binary search implementation math number theory Statement B Codeforces Round 142 (Div. 2) {230} PROGRAMMING Codeforces Round #142 Problem Analysis 1300
20896 LCM Challenge number theory Statement A Codeforces Round 146 (Div. 1) {235} PROGRAMMING Codeforces Round #146 Tutorial 1600
884 Number Challenge combinatorics dp implementation math number theory Statement E Codeforces Round 146 (Div. 1) {235} PROGRAMMING Codeforces Round #146 Tutorial 2600
16874 Easy Number Challenge implementation number theory Statement B Codeforces Round 146 (Div. 2) {236} PROGRAMMING Codeforces Round #146 Tutorial 1300
6632 Primes on Interval binary search number theory two pointers Statement C Codeforces Round 147 (Div. 2) {237} PROGRAMMING Codeforces Round #147 (Div. 2) Разбор Задач 1600
1325 Hydra graphs sortings Statement B Codeforces Round 150 (Div. 1) {243} PROGRAMMING Editorial for Codeforces Round #150 2100
10216 Buggy Sorting constructive algorithms greedy sortings Statement A Codeforces Round 151 (Div. 2) {246} PROGRAMMING Codeforces Round #151 (Div. 2) Tutorial 1000
5797 Chilly Willy math number theory Statement B Codeforces Round 152 (Div. 2) {248} PROGRAMMING Разбор задач Codeforces Round #152 1400
1124 Number Transformation dp greedy number theory Statement C Codeforces Round 153 (Div. 1) {251} PROGRAMMING Editorial of Codeforces Round #153 2500
11985 Good Sequences dp number theory Statement B Codeforces Round 162 (Div. 1) {264} PROGRAMMING Tutorial 1700
9495 Subtractions math number theory Statement A Codeforces Testing Round 5 {267} PROGRAMMING 1100
118 String Theory Statement E Codeforces Round 165 (Div. 1) {269} PROGRAMMING Разбор Codeforces Round #165 3100
15353 Prime Matrix binary search brute force math number theory Statement B Codeforces Round 166 (Div. 2) {271} PROGRAMMING editroal 1400
597 Three Horses constructive algorithms math number theory Statement E Codeforces Round 166 (Div. 2) {271} PROGRAMMING 6662 2500
1590 Beautiful Decomposition dp games greedy number theory Statement E Codeforces Round 171 (Div. 2) {279} PROGRAMMING Codeforces Round #171 (Div. 2) Разбор Задач 2100
640 Cows and Cool Sequences dp math number theory Statement D Codeforces Round 174 (Div. 1) {283} PROGRAMMING Editorial for Codeforces #174 2400
7324 Cows and Primitive Roots implementation math number theory Statement A Codeforces Round 174 (Div. 2) {284} PROGRAMMING Editorial for Codeforces #174 1400
632 Cube Problem brute force math number theory Statement C Croc Champ 2013 - Round 2 {293} PROGRAMMING Croc Champ 2013 — Round 2 — Editorial 2300
4312 Shaass and Lights combinatorics number theory Statement C Codeforces Round 178 (Div. 2) {294} PROGRAMMING Codeforces Round #178 Editorial 1900
378 Shaass and Painter Robot brute force implementation number theory Statement D Codeforces Round 178 (Div. 2) {294} PROGRAMMING Codeforces Round #178 Editorial 2700
9425 Ksusha and Array brute force number theory sortings Statement A Croc Champ 2013 - Round 2 (Div. 2 Edition) {299} PROGRAMMING Croc Champ 2013 — Round 2 — Editorial 1000
1102 Empire Strikes Back binary search math number theory Statement E Codeforces Round 181 (Div. 2) {300} PROGRAMMING English Tutorial 2400
350 Rotatable Number math number theory Statement D Codeforces Round 183 (Div. 1) {303} PROGRAMMING Codeforces Round #183 Editorial 2500
965 Minimum Modular brute force graphs math number theory Statement C Codeforces Round 183 (Div. 1) {303} PROGRAMMING Codeforces Round #183 Editorial 2700
619 White, Black and White Again combinatorics number theory Statement C Testing Round 6 {306} PROGRAMMING 2200
64806 Ilya and Bank Account implementation number theory Statement A Codeforces Round 186 (Div. 2) {313} PROGRAMMING Tutorial 900
2654 Vasily the Bear and Sequence brute force greedy implementation number theory Statement C Codeforces Round 195 (Div. 2) {336} PROGRAMMING Tutorial Codeforces Round #195 (Div. 2) 1800
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
10050 Routine Problem greedy math number theory Statement B Codeforces Round 196 (Div. 2) {337} PROGRAMMING Codeforces Round #196 — Problems Analysis 1400
5222 Quiz binary search greedy math matrices number theory Statement C Codeforces Round 196 (Div. 2) {337} PROGRAMMING Codeforces Round #196 — Problems Analysis 1700
1127 Divisor Tree brute force number theory trees Statement E Codeforces Round 196 (Div. 2) {337} PROGRAMMING Codeforces Round #196 — Problems Analysis 2400
1392 GCD Table chinese remainder theorem math number theory Statement D Codeforces Round 196 (Div. 1) {338} PROGRAMMING Codeforces Round #196 — Problems Analysis 2700
10064 Rational Resistance math number theory Statement A Codeforces Round 200 (Div. 1) {343} PROGRAMMING Codeforces Round #200 Tutorial 1600
9318 Alice and Bob games math number theory Statement A Codeforces Round 201 (Div. 1) {346} PROGRAMMING Codeforces Round #201 Editorial 1600
293 Doodle Jump math number theory Statement E Codeforces Round 201 (Div. 1) {346} PROGRAMMING Codeforces Round #201 Editorial 3000
2280 Apple Tree dfs and similar number theory trees Statement B Codeforces Round 202 (Div. 1) {348} PROGRAMMING Editorial for Codeforces Round #202 2400
5251 Find Maximum implementation math number theory Statement C Codeforces Round 205 (Div. 2) {353} PROGRAMMING 9145 1600
3327 Vasya and Beautiful Arrays brute force dp number theory Statement C Codeforces Round 206 (Div. 1) {354} PROGRAMMING Codeforces Round #206 — Editorial 2000
3551 Prime Number math number theory Statement C Codeforces Round 209 (Div. 2) {359} PROGRAMMING Editorial Codeforces Round #209 (Div. 2) 2000
485 Levko and Sets number theory Statement D Codeforces Round 210 (Div. 1) {360} PROGRAMMING Codeforces Round #210 editorial 2600
8781 Levko and Permutation constructive algorithms math number theory Statement B Codeforces Round 210 (Div. 2) {361} PROGRAMMING Codeforces Round #210 editorial 1200
641 Beautiful Set brute force number theory Statement C Codeforces Round 213 (Div. 1) {364} PROGRAMMING Codeforces Round #213 Editorial 2500
12515 Fox Dividing Cheese math number theory Statement B Codeforces Round 218 (Div. 2) {371} PROGRAMMING Codeforces Round #218 (Div. 2): Tutorial 1400
5331 Divisible by Seven math number theory Statement A Codeforces Round 221 (Div. 1) {375} PROGRAMMING Codeforces Round #221 Tutorial 1800
8850 Tree and Queries data structures dfs and similar trees Statement D Codeforces Round 221 (Div. 1) {375} PROGRAMMING Codeforces Round #221 Tutorial 2400
10545 Bear and Prime Numbers binary search brute force data structures dp implementation math number theory Statement C Codeforces Round 226 (Div. 2) {385} PROGRAMMING Codeforces Round #226 (Div. 2) — Editorial 1800
496 Fox and Perfect Sets math Statement D Codeforces Round 228 (Div. 1) {388} PROGRAMMING Codeforces Round #228 — Editorial 2700
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)
1796 On Changing Tree data structures graphs trees Statement C Codeforces Round 232 (Div. 1) {396} PROGRAMMING 1500.0 Codeforces Round #232 Editorial (restored)
1189 On Sum of Fractions math number theory Statement B Codeforces Round 232 (Div. 1) {396} PROGRAMMING 1000.0 Codeforces Round #232 Editorial (restored)
219 Tree and Array constructive algorithms Statement C Codeforces Round 233 (Div. 1) {398} PROGRAMMING 1500.0 Codeforces Round #233 Editorial
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
2782 Upgrading Array dp greedy math number theory Statement D Codeforces Round 236 (Div. 2) {402} PROGRAMMING Editorial Codeforces Round #236 2000
29009 Mashmokh and ACM combinatorics dp number theory Statement B Codeforces Round 240 (Div. 1) {414} PROGRAMMING Codeforces Round #240 Editorial 1500
10546 Mashmokh and Numbers constructive algorithms number theory Statement A Codeforces Round 240 (Div. 1) {414} PROGRAMMING Codeforces Round #240 Editorial 1500
1089 Population Size greedy implementation math Statement D Codeforces Round 241 (Div. 2) {416} PROGRAMMING Codeforces Round #241 — editorial 2300
2126 The Child and Binary Tree combinatorics divide and conquer fft number theory Statement E Codeforces Round 250 (Div. 1) {438} PROGRAMMING Tutorial 3100
4167 Devu and Partitioning of the Array brute force constructive algorithms implementation number theory Statement C Codeforces Round 251 (Div. 2) {439} PROGRAMMING Codeforces Round #251 Editorial 1700
8886 Forgotten Episode implementation Statement A Testing Round 10 {440} PROGRAMMING 1000
3914 DZY Loves Fibonacci Numbers data structures math number theory Statement C Codeforces Round #FF (Div. 1) {446} PROGRAMMING Codeforces Round #FF(255) Editorial 2600
1633 Divisors brute force dfs and similar implementation number theory Statement E Codeforces Round 256 (Div. 2) {448} PROGRAMMING Codeforces Round #256 — Разбор 2500
2524 Jzzhu and Apples constructive algorithms number theory Statement C Codeforces Round 257 (Div. 1) {449} PROGRAMMING Codeforces Round #257 Editorial 2500
305 Jzzhu and Squares dp math number theory Statement E Codeforces Round 257 (Div. 1) {449} PROGRAMMING Codeforces Round #257 Editorial 2900
4495 Devu and Flowers bitmasks combinatorics number theory Statement E Codeforces Round 258 (Div. 2) {451} PROGRAMMING Codeforces Round #258 Editorial 2400
18512 Fedya and Maths math number theory Statement B Codeforces Round 260 (Div. 2) {456} PROGRAMMING Codeforces Round #260 — Editorial 1200
5967 Pashmak and Graph dp sortings Statement E Codeforces Round 261 (Div. 2) {459} PROGRAMMING Codeforces Round #261 Editorial 2100
13359 Little Dima and Equation brute force implementation math number theory Statement B Codeforces Round 262 (Div. 2) {460} PROGRAMMING 13465 1500
1036 Little Victor and Set brute force constructive algorithms math Statement D Codeforces Round 262 (Div. 2) {460} PROGRAMMING 13465 2500
1739 Caisa and Tree brute force dfs and similar math number theory trees Statement E Codeforces Round 264 (Div. 2) {463} PROGRAMMING CF 264 Div 2 Tutorial 2400
70465 Design Tutorial: Learn from Math math number theory Statement A Codeforces Round 270 {472} PROGRAMMING Editorial 900
11492 Ant colony data structures math number theory Statement F Codeforces Round 271 (Div. 2) {474} PROGRAMMING Codeforces Round #271 (Div. 2) Editorial 2200
24841 Counterexample brute force implementation math number theory Statement A Codeforces Round 275 (Div. 2) {483} PROGRAMMING Codeforces Round #275 Editorial 1100
3075 Prefix Product Sequence constructive algorithms math number theory Statement C Codeforces Round 278 (Div. 1) {487} PROGRAMMING Tutorial 2600
9462 Hacking Cypher brute force math number theory strings Statement C Codeforces Round 279 (Div. 2) {490} PROGRAMMING Codeforces Round #279 (Div. 2) Editorial 1700
2313 Chocolate brute force dfs and similar math meet-in-the-middle number theory Statement D Codeforces Round 279 (Div. 2) {490} PROGRAMMING Codeforces Round #279 (Div. 2) Editorial 1900
8248 Modular Equations math number theory Statement B Codeforces Round 282 (Div. 2) {495} PROGRAMMING Tutorial 1600
1242 Traffic Jams in the Land data structures dp number theory Statement D Codeforces Round 284 (Div. 1) {498} PROGRAMMING Codeforces Round #284 Editorial 2400
4144 Array and Operations flows graph matchings number theory Statement C Codeforces Round 284 (Div. 1) {498} PROGRAMMING Codeforces Round #284 Editorial 2400
44689 Lecture implementation strings Statement B Codeforces Round 284 (Div. 2) {499} PROGRAMMING 15353 1000
168 New Year Running number theory trees Statement G Good Bye 2014 {500} PROGRAMMING Tutorial 2 3000
7760 Drazil and His Happy Friends brute force dsu meet-in-the-middle number theory Statement B Codeforces Round 292 (Div. 2) {515} PROGRAMMING Codeforces Round #292 Editorial 1400
605 Drazil and His Happy Friends math number theory Statement E Codeforces Round 292 (Div. 1) {516} PROGRAMMING 16468 3000
20690 A and B and Team Training greedy implementation math number theory Statement C Codeforces Round 294 (Div. 2) {519} PROGRAMMING Editorial 1300
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
537 Superhero's Job dfs and similar dp hashing math number theory Statement D VK Cup 2015 - Round 3 (unofficial online mirror, Div. 1 only) {542} PROGRAMMING 17697 2600
13720 Soldier and Number Game constructive algorithms dp math number theory Statement D Codeforces Round 304 (Div. 2) {546} PROGRAMMING Codeforces Round #304 (Div.2) editorial 1700
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
5861 Vanya and Scales brute force dp greedy math meet-in-the-middle number theory Statement C Codeforces Round 308 (Div. 2) {552} PROGRAMMING Codeforces #308 (Div. 2) Editorial 1800
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
4291 Clique in the Divisibility Graph dp math number theory Statement F VK Cup 2015 - Finals, online mirror {566} PROGRAMMING Editorial for VK Cup 2015 — Finals 1600
5397 Primes or Palindromes? brute force implementation math number theory Statement A Codeforces Round 315 (Div. 1) {568} PROGRAMMING Codeforces Round #315 Editorial 1700
2382 Symmetric and Transitive combinatorics dp math Statement B Codeforces Round 315 (Div. 1) {568} PROGRAMMING Codeforces Round #315 Editorial 2100
18154 Bear and Poker implementation math number theory Statement A Codeforces Round 318 [RussianCodeCup Thanks-Round] (Div. 1) {573} PROGRAMMING Codeforces Round #318 [RussianCodeCup Thanks-Round] Editorial 1400
1876 Bots combinatorics number theory Statement H Bubble Cup 8 - Finals [Online Mirror] {575} PROGRAMMING Bubble Cup finals 2015 Results and Editorial 1800
15888 Vasya and Petya's Game math number theory Statement A Codeforces Round 319 (Div. 1) {576} PROGRAMMING Editorial Codeforces Round #319 1500
45166 Multiplication Table implementation number theory Statement A Codeforces Round 319 (Div. 2) {577} PROGRAMMING Editorial Codeforces Round #319 1100
8332 GCD Table constructive algorithms greedy number theory Statement A Codeforces Round 323 (Div. 1) {582} PROGRAMMING Codeforces Round #323 Editorial 1700
794 Superior Periodic Subarrays number theory Statement C Codeforces Round 323 (Div. 1) {582} PROGRAMMING Codeforces Round #323 Editorial 2900
739 Number of Binominal Coefficients dp math number theory Statement D Codeforces Round 323 (Div. 1) {582} PROGRAMMING Codeforces Round #323 Editorial 3100
11076 Dima and Lisa brute force math number theory Statement D Codeforces Round 324 (Div. 2) {584} PROGRAMMING Tutorial 1700
1062 Alice, Bob, Oranges and Apples number theory Statement C Codeforces Round 325 (Div. 1) {585} PROGRAMMING Разбор Codeforces Round #325 2400
1220 Present for Vitalik the Philatelist combinatorics math number theory Statement E Codeforces Round 325 (Div. 1) {585} PROGRAMMING Разбор Codeforces Round #325 2800
2007 REQ data structures number theory Statement D Codeforces Round 330 (Div. 1) {594} PROGRAMMING Codeforces Round #330 (Div.1 + Div.2) Editorial 2500
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
4273 Multipliers math number theory Statement D Codeforces Round 338 (Div. 2) {615} PROGRAMMING Codeforces Round #338 (Div. 2) editorial 1900
3476 Sum of Remainders implementation math number theory Statement E Educational Codeforces Round 5 {616} PROGRAMMING Editorial of Educational Codeforces Round 5 2200
6218 Wet Shark and Flowers combinatorics math number theory probabilities Statement C Codeforces Round 341 (Div. 2) {621} PROGRAMMING 1700
2355 Array GCD dp greedy number theory Statement B AIM Tech Round (Div. 1) {623} PROGRAMMING AIM Tech Round Tutorial 2400
4613 Block Towers brute force greedy math number theory Statement C 8VC Venture Cup 2016 - Elimination Round {626} PROGRAMMING 23522 1600
12671 Divisibility math number theory Statement J Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1200
9570 Game games math Statement R Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1300
6320 Indivisibility math number theory Statement K Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1700
92881 Again Twenty Five! number theory Statement A Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 800
4562 Longest Subsequence brute force math number theory Statement D Educational Codeforces Round 9 {632} PROGRAMMING 43493 2200
14656 Ebony and Ivory brute force math number theory Statement A Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 1200
7225 A Trivial Problem brute force constructive algorithms math number theory Statement B Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 1300
874 Yash And Trees bitmasks data structures dfs and similar math number theory Statement G Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 2700
1570 Little Artem and Random Variable dp implementation math probabilities Statement D VK Cup 2016 - Round 2 {641} PROGRAMMING VK Cup 2016 — Раунд 2 (editorial) 2300
966 Cowslip Collections combinatorics math number theory Statement F CROC 2016 - Elimination Round {645} PROGRAMMING Editorial for CROC 2016 Elimination Round 2500
2172 Table Compression dfs and similar dp dsu graphs greedy Statement C Codeforces Round 345 (Div. 1) {650} PROGRAMMING Codeforces Round #345: editorial 2300
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
10251 Co-prime Array greedy implementation math number theory Statement A Educational Codeforces Round 11 {660} PROGRAMMING Editorial of Educational Codeforces Round 11 1300
21532 Complicated GCD math number theory Statement A Codeforces Round 347 (Div. 2) {664} PROGRAMMING Editorial for CROC 2016 Finals and Codeforces Round #347 900
4164 Simple Subset constructive algorithms greedy number theory Statement D Educational Codeforces Round 12 {665} PROGRAMMING Editorial 2000
748 Four Divisors dp math number theory Statement F Educational Codeforces Round 12 {665} PROGRAMMING Editorial 2600
773 Ultimate Weirdness of an Array data structures number theory Statement C Codeforces Round 352 (Div. 1) {671} PROGRAMMING Codeforces Round #352 Editorial 2700
10991 Joty and Chocolate implementation math number theory Statement C Educational Codeforces Round 13 {678} PROGRAMMING Editorial 1600
5393 Iterated Linear Function math number theory Statement D Educational Codeforces Round 13 {678} PROGRAMMING Editorial 1800
23956 Alyona and Numbers constructive algorithms math number theory Statement A Codeforces Round 358 (Div. 2) {682} PROGRAMMING 45491 1200
6801 Remainders Game chinese remainder theorem math number theory Statement B Codeforces Round 360 (Div. 1) {687} PROGRAMMING Codeforces Round #360 Editorial [+ Challenges!] 1900
1433 Couple Cover brute force dp number theory Statement F Educational Codeforces Round 14 {691} PROGRAMMING Editorial of Educational Codeforces Round 14 2300
487 Coprime Permutation combinatorics number theory Statement F Codeforces Round 363 (Div. 1) {698} PROGRAMMING Solution 3000
666 Mishka and Divisors dp number theory Statement E Codeforces Round 365 (Div. 2) {703} PROGRAMMING Codeforces Round #365 (Div. 2) Editorial 2900
524 Black Widow dp graphs implementation math Statement C Codeforces Round 366 (Div. 1) {704} PROGRAMMING Tutorial 2800
13465 Pythagorean Triples math number theory Statement C Codeforces Round 368 (Div. 2) {707} PROGRAMMING 46662 1500
1359 ZS and The Birthday Paradox math number theory probabilities Statement E Codeforces Round 369 (Div. 2) {711} PROGRAMMING 46830 2400
431 Festival Organization math number theory Statement A Bubble Cup 9 - Finals [Online Mirror] {717} PROGRAMMING Tutorial 3000
605 Cyclic Cipher chinese remainder theorem data structures implementation number theory two pointers Statement F Intel Code Challenge Elimination Round (Div. 1 + Div. 2, combined) {722} PROGRAMMING Tutorial 2800
2264 Ray Tracing greedy hashing implementation math number theory sortings Statement C Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} PROGRAMMING Tutorial 1800
1500 Xor-matic Number of the Graph bitmasks graphs math number theory trees Statement G Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} PROGRAMMING Tutorial 2600
3137 Video Cards brute force data structures implementation math number theory Statement F Codeforces Round 376 (Div. 2) {731} PROGRAMMING 47840 1900
8739 Urbanization greedy number theory sortings Statement B Codeforces Round 382 (Div. 2) {735} PROGRAMMING Codeforces Round #382 Editorial 1200
15675 Taxes math number theory Statement D Codeforces Round 382 (Div. 2) {735} PROGRAMMING Codeforces Round #382 Editorial 1600
51720 Arpa’s hard exam and Mehrdad’s naive cheat implementation math number theory Statement A Codeforces Round 383 (Div. 2) {742} PROGRAMMING Test data 1000
10040 Arpa’s obvious problem and Mehrdad’s terrible solution brute force math number theory Statement B Codeforces Round 383 (Div. 2) {742} PROGRAMMING Test data 1500
13385 Vladik and fractions brute force constructive algorithms math number theory Statement C Codeforces Round 384 (Div. 2) {743} PROGRAMMING Codeforces Round #384 Editorial 1500
56864 Bachgold Problem greedy implementation math number theory Statement A Codeforces Round 388 (Div. 2) {749} PROGRAMMING Tutorial 700
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
19752 PolandBall and Hypothesis brute force graphs math number theory Statement A 8VC Venture Cup 2017 - Elimination Round {755} PROGRAMMING 8VC Venture Cup 2017 — Elimination Round [Editorial] 900
128 Long number expression parsing math number theory Statement F 8VC Venture Cup 2017 - Final Round {756} PROGRAMMING 8VC Venture Cup 2017 — Final Round and Codeforces Round #393 Editorial 3200
11403 Bash's Big Day greedy math number theory Statement B 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 1400
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
10692 Blown Garland brute force implementation number theory Statement B Codeforces Round 392 (Div. 2) {758} PROGRAMMING Codeforces Round #392 (Div. 2) Editorial 1200
712 Geometrical Progression brute force math number theory Statement F Codeforces Round 392 (Div. 2) {758} PROGRAMMING Codeforces Round #392 (Div. 2) Editorial 2500
25634 k-th divisor math number theory Statement A Educational Codeforces Round 17 {762} PROGRAMMING Tutorial 1500
776 Timofey and remoduling brute force implementation math number theory Statement C Codeforces Round 395 (Div. 1) {763} PROGRAMMING Codeforces Round #395 [Editorial] 2500
115 Math, math everywhere brute force dp math meet-in-the-middle number theory Statement G Codeforces Round 397 by Kaspersky Lab and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {765} PROGRAMMING Codeforces Round #397 Editorial 2800
38252 Mahmoud and a Triangle constructive algorithms geometry greedy math number theory sortings Statement B Codeforces Round 396 (Div. 2) {766} PROGRAMMING Codeforces round #396 editorial 1100
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
1443 Vulnerable Kerbals constructive algorithms dp graphs math number theory Statement C VK Cup 2017 - Round 2 {772} PROGRAMMING VK Cup Round 2 + Codeforces Round #409 Tutorial 2400
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
261 Big Number and Remainder *special math number theory Statement E VK Cup 2017 - Wild Card Round 1 {774} PROGRAMMING VK Cup 2017 — Уайлд-кард раунд 1 — Разбор 2400
152 Pens And Days Of Week *special binary search number theory Statement F VK Cup 2017 - Wild Card Round 1 {774} PROGRAMMING VK Cup 2017 — Уайлд-кард раунд 1 — Разбор 2600
197 Perfectionist Arkadiy *special number theory Statement G VK Cup 2017 - Wild Card Round 1 {774} PROGRAMMING VK Cup 2017 — Уайлд-кард раунд 1 — Разбор 2900
25577 Sherlock and his girlfriend constructive algorithms number theory Statement B 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 1200
2434 The Holmes Children math number theory Statement E 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 2100
3656 Anton and School - 2 combinatorics dp math number theory Statement D Codeforces Round 404 (Div. 2) {785} PROGRAMMING Editorial 2200
12174 The Monster brute force math number theory Statement A Codeforces Round 406 (Div. 2) {787} PROGRAMMING Codeforces Round #406 Editorial 1300
4982 Divide by Three dp greedy math number theory Statement C Educational Codeforces Round 18 {792} PROGRAMMING Educational Codeforces Round 18 - Editorial 2000
1263 Colored Balls greedy math number theory Statement E Educational Codeforces Round 18 {792} PROGRAMMING Educational Codeforces Round 18 - Editorial 2400
19773 k-Factorization implementation math number theory Statement A Educational Codeforces Round 19 {797} PROGRAMMING 51588 1100
6363 Mike and gcd problem dp greedy number theory Statement C Codeforces Round 410 (Div. 2) {798} PROGRAMMING Codeforces Round #410 (Div. 2) Editorial 1700
4600 Coprime Subsequences bitmasks combinatorics number theory Statement F Educational Codeforces Round 20 {803} PROGRAMMING 51768 2100
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
853 Surprise me! divide and conquer math number theory trees Statement E Codeforces Round 415 (Div. 1) {809} PROGRAMMING 52099 3000
6807 Treasure Hunt implementation math number theory Statement A Educational Codeforces Round 23 {817} PROGRAMMING 52638 1200
2673 Card Game Again binary search data structures number theory two pointers Statement E Educational Codeforces Round 24 {818} PROGRAMMING 52991 2000
308 Mister B and Astronomers number theory Statement D Codeforces Round 421 (Div. 1) {819} PROGRAMMING Codeforces Round #421 Editorial 2900
230 Mister B and Beacons on Field number theory Statement C Codeforces Round 421 (Div. 1) {819} PROGRAMMING Codeforces Round #421 Editorial 3000
3282 My pretty girl Noora brute force dp greedy math number theory Statement D Codeforces Round 422 (Div. 2) {822} PROGRAMMING Codeforces Round #422 (Div. 2) Editorial 1800
373 Madness constructive algorithms dfs and similar trees Statement F Codeforces Round 422 (Div. 2) {822} PROGRAMMING Codeforces Round #422 (Div. 2) Editorial 2700
36677 I'm bored with life implementation math number theory Statement A Codeforces Round 422 (Div. 2) {822} PROGRAMMING Codeforces Round #422 (Div. 2) Editorial 800
1306 Bamboo Partition brute force data structures implementation math number theory sortings two pointers Statement C Codeforces Round 424 (Div. 1, rated, based on VK Cup Finals) {830} PROGRAMMING Codeforces Round #424 Editorial 2500
6553 The Meaningless Game math number theory Statement A Codeforces Round 426 (Div. 1) {833} PROGRAMMING Codeforces Round #426 Editorial 1700
2057 Vasya's Function binary search implementation math Statement E Educational Codeforces Round 26 {837} PROGRAMMING 53662 2200
1137 Airplane Arrangements math number theory Statement D IndiaHacks 2nd Elimination 2017 (unofficial, unrated mirror, ICPC rules) {838} PROGRAMMING 53736 2700
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
3753 Ilya And The Tree dfs and similar graphs math number theory trees Statement C Codeforces Round 430 (Div. 2) {842} PROGRAMMING Tutorial Codeforces Round #430 (Div. 2) 2000
2127 Arpa and a list of numbers implementation number theory Statement B Codeforces Round 432 (Div. 1, based on IndiaHacks Final Round 2017) {850} PROGRAMMING Codeforces Round #432 editorial 2000
652 Product transformation combinatorics math number theory Statement F Bubble Cup X - Finals [Online Mirror] {852} PROGRAMMING Tutorial 2300
1611 Set Theory brute force constructive algorithms Statement A Russian Code Cup 2017 - Finals [Unofficial Mirror, Div. 1 Only Recommended, Teams Allowed] {856} PROGRAMMING Tutorial 1600