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5806 Line math number theory Statement C Codeforces Beta Round 7 {7} PROGRAMMING 1800
22498 Noldbach problem brute force math number theory Statement A Codeforces Beta Round 17 {17} PROGRAMMING Codeforces Beta Round #17 Tutorial 1100
1756 First Digit Law dp math probabilities Statement C Codeforces Beta Round 50 {54} PROGRAMMING Codeforces Beta Round #50: Editorial for problem E 2000
3780 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
7465 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
439 Morrowindows math number theory Statement E Codeforces Beta Round 66 {73} PROGRAMMING Codeforces Beta Round #66 editorial: Problems D, E, F 2300
1093 Numbers dp math number theory Statement D Codeforces Beta Round 72 (Div. 1 Only) {83} PROGRAMMING разбор E 2400
16844 Toy Army math number theory Statement A Codeforces Beta Round 72 (Div. 2 Only) {84} PROGRAMMING 1000
556 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
1511 Double Happiness brute force math number theory Statement C Codeforces Beta Round 86 (Div. 1 Only) {113} PROGRAMMING Codeforces Beta Round #86 Editorial 2200
2558 Pairs of Numbers brute force dfs and similar math number theory Statement B Codeforces Testing Round 3 {134} PROGRAMMING 1800
8748 Win or Freeze games math number theory Statement A Codeforces Round 107 (Div. 1) {150} PROGRAMMING Tutorial 1600
6324 Colliders math number theory Statement B Codeforces Round 109 (Div. 1) {154} PROGRAMMING Codeforces Round #109: editorial 1700
489 Divisibility Rules math number theory Statement B Codeforces Round 116 (Div. 2, ACM-ICPC Rules) {180} PROGRAMMING 2300
547 Visit of the Great math number theory Statement D Codeforces Round 118 (Div. 1) {185} PROGRAMMING Tutorial 2600
374 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
714 Martian Luck math number theory Statement E Codeforces Round 133 (Div. 2) {216} PROGRAMMING Editorial for Codeforces Round #133 2300
3053 Reducing Fractions implementation math number theory sortings Statement C Codeforces Round 137 (Div. 2) {222} PROGRAMMING Разбор задач Codeforces Round #137 (Div. 2) 2000
1772 Partial Sums combinatorics math number theory Statement C Codeforces Round 138 (Div. 1) {223} PROGRAMMING Tutorial 2200
931 Unsolvable math number theory Statement E Codeforces Round 139 (Div. 2) {225} PROGRAMMING Tutorial 2100
1052 Anniversary data structures implementation math matrices number theory Statement C Codeforces Round 140 (Div. 1) {226} PROGRAMMING Codeforces Round #140 Editorial 2100
626 Gifts combinatorics dp math probabilities Statement E Codeforces Round 142 (Div. 1) {229} PROGRAMMING Codeforces Round #142 Problem Analysis 2500
100739 T-primes binary search implementation math number theory Statement B Codeforces Round 142 (Div. 2) {230} PROGRAMMING Codeforces Round #142 Problem Analysis 1300
993 Number Challenge combinatorics dp implementation math number theory Statement E Codeforces Round 146 (Div. 1) {235} PROGRAMMING Codeforces Round #146 Tutorial 2600
5890 Chilly Willy math number theory Statement B Codeforces Round 152 (Div. 2) {248} PROGRAMMING Разбор задач Codeforces Round #152 1400
9809 Subtractions math number theory Statement A Codeforces Testing Round 5 {267} PROGRAMMING 1100
15873 Prime Matrix binary search brute force math number theory Statement B Codeforces Round 166 (Div. 2) {271} PROGRAMMING editroal 1400
690 Three Horses constructive algorithms math number theory Statement E Codeforces Round 166 (Div. 2) {271} PROGRAMMING 6662 2500
718 Cows and Cool Sequences dp math number theory Statement D Codeforces Round 174 (Div. 1) {283} PROGRAMMING Editorial for Codeforces #174 2400
7482 Cows and Primitive Roots implementation math number theory Statement A Codeforces Round 174 (Div. 2) {284} PROGRAMMING Editorial for Codeforces #174 1400
700 Cube Problem brute force math number theory Statement C Croc Champ 2013 - Round 2 {293} PROGRAMMING Croc Champ 2013 — Round 2 — Editorial 2300
1143 Empire Strikes Back binary search math number theory Statement E Codeforces Round 181 (Div. 2) {300} PROGRAMMING English Tutorial 2400
441 Rotatable Number math number theory Statement D Codeforces Round 183 (Div. 1) {303} PROGRAMMING Codeforces Round #183 Editorial 2500
989 Minimum Modular brute force graphs math number theory Statement C Codeforces Round 183 (Div. 1) {303} PROGRAMMING Codeforces Round #183 Editorial 2700
66711 Ilya and Bank Account implementation number theory Statement A Codeforces Round 186 (Div. 2) {313} PROGRAMMING Tutorial 900
1246 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
10168 Routine Problem greedy math number theory Statement B Codeforces Round 196 (Div. 2) {337} PROGRAMMING Codeforces Round #196 — Problems Analysis 1400
5282 Quiz binary search greedy math matrices number theory Statement C Codeforces Round 196 (Div. 2) {337} PROGRAMMING Codeforces Round #196 — Problems Analysis 1700
1510 GCD Table chinese remainder theorem math number theory Statement D Codeforces Round 196 (Div. 1) {338} PROGRAMMING Codeforces Round #196 — Problems Analysis 2700
10207 Rational Resistance math number theory Statement A Codeforces Round 200 (Div. 1) {343} PROGRAMMING Codeforces Round #200 Tutorial 1600
9443 Alice and Bob games math number theory Statement A Codeforces Round 201 (Div. 1) {346} PROGRAMMING Codeforces Round #201 Editorial 1600
388 Doodle Jump math number theory Statement E Codeforces Round 201 (Div. 1) {346} PROGRAMMING Codeforces Round #201 Editorial 3000
5309 Find Maximum implementation math number theory Statement C Codeforces Round 205 (Div. 2) {353} PROGRAMMING 9145 1600
3632 Prime Number math number theory Statement C Codeforces Round 209 (Div. 2) {359} PROGRAMMING Editorial Codeforces Round #209 (Div. 2) 2000
8894 Levko and Permutation constructive algorithms math number theory Statement B Codeforces Round 210 (Div. 2) {361} PROGRAMMING Codeforces Round #210 editorial 1200
12745 Fox Dividing Cheese math number theory Statement B Codeforces Round 218 (Div. 2) {371} PROGRAMMING Codeforces Round #218 (Div. 2): Tutorial 1400
5410 Divisible by Seven math number theory Statement A Codeforces Round 221 (Div. 1) {375} PROGRAMMING Codeforces Round #221 Tutorial 1800
10855 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
1655 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)
1202 On Sum of Fractions math number theory Statement B Codeforces Round 232 (Div. 1) {396} PROGRAMMING 1000.0 Codeforces Round #232 Editorial (restored)
2815 Upgrading Array dp greedy math number theory Statement D Codeforces Round 236 (Div. 2) {402} PROGRAMMING Editorial Codeforces Round #236 2000
4103 DZY Loves Fibonacci Numbers data structures math number theory Statement C Codeforces Round #FF (Div. 1) {446} PROGRAMMING Codeforces Round #FF(255) Editorial 2600
357 Jzzhu and Squares dp math number theory Statement E Codeforces Round 257 (Div. 1) {449} PROGRAMMING Codeforces Round #257 Editorial 2900
18964 Fedya and Maths math number theory Statement B Codeforces Round 260 (Div. 2) {456} PROGRAMMING Codeforces Round #260 — Editorial 1200
13550 Little Dima and Equation brute force implementation math number theory Statement B Codeforces Round 262 (Div. 2) {460} PROGRAMMING 13465 1500
1796 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
72474 Design Tutorial: Learn from Math math number theory Statement A Codeforces Round 270 {472} PROGRAMMING Editorial 900
12524 Ant colony data structures math number theory Statement F Codeforces Round 271 (Div. 2) {474} PROGRAMMING Codeforces Round #271 (Div. 2) Editorial 2200
25144 Counterexample brute force implementation math number theory Statement A Codeforces Round 275 (Div. 2) {483} PROGRAMMING Codeforces Round #275 Editorial 1100
3174 Prefix Product Sequence constructive algorithms math number theory Statement C Codeforces Round 278 (Div. 1) {487} PROGRAMMING Tutorial 2600
9542 Hacking Cypher brute force math number theory strings Statement C Codeforces Round 279 (Div. 2) {490} PROGRAMMING Codeforces Round #279 (Div. 2) Editorial 1700
2336 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
8511 Modular Equations math number theory Statement B Codeforces Round 282 (Div. 2) {495} PROGRAMMING Tutorial 1600
680 Drazil and His Happy Friends math number theory Statement E Codeforces Round 292 (Div. 1) {516} PROGRAMMING 16468 3000
20862 A and B and Team Training greedy implementation math number theory Statement C Codeforces Round 294 (Div. 2) {519} PROGRAMMING Editorial 1300
2156 Pluses everywhere combinatorics dp math number theory Statement E Codeforces Round 295 (Div. 2) {520} PROGRAMMING Codeforces Round #295 Editorial (now with bonuses!) 2500
543 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
14172 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
3592 Mike and Foam bitmasks combinatorics dp math number theory Statement C Codeforces Round 305 (Div. 1) {547} PROGRAMMING Codeforces Round #305 Editorial 2700
2150 GukiZ and Binary Operations combinatorics implementation math matrices number theory Statement D Codeforces Round 307 (Div. 2) {551} PROGRAMMING Tutorial 2400
5907 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
8564 Gerald and Giant Chess combinatorics dp math number theory Statement C Codeforces Round 313 (Div. 1) {559} PROGRAMMING Codeforces Round 313 — Extended editoral 2500
4373 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
5433 Primes or Palindromes? brute force implementation math number theory Statement A Codeforces Round 315 (Div. 1) {568} PROGRAMMING Codeforces Round #315 Editorial 1700
18901 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
16180 Vasya and Petya's Game math number theory Statement A Codeforces Round 319 (Div. 1) {576} PROGRAMMING Editorial Codeforces Round #319 1500
848 Number of Binominal Coefficients dp math number theory Statement D Codeforces Round 323 (Div. 1) {582} PROGRAMMING Codeforces Round #323 Editorial 3100
11421 Dima and Lisa brute force math number theory Statement D Codeforces Round 324 (Div. 2) {584} PROGRAMMING Tutorial 1700
1294 Present for Vitalik the Philatelist combinatorics math number theory Statement E Codeforces Round 325 (Div. 1) {585} PROGRAMMING Разбор Codeforces Round #325 2800
2748 Moodular Arithmetic combinatorics dfs and similar dsu math number theory Statement B Codeforces Round 334 (Div. 1) {603} PROGRAMMING Codeforces Round #334 Editorial 2000
4367 Multipliers math number theory Statement D Codeforces Round 338 (Div. 2) {615} PROGRAMMING Codeforces Round #338 (Div. 2) editorial 1900
3769 Sum of Remainders implementation math number theory Statement E Educational Codeforces Round 5 {616} PROGRAMMING Editorial of Educational Codeforces Round 5 2200
6546 Wet Shark and Flowers combinatorics math number theory probabilities Statement C Codeforces Round 341 (Div. 2) {621} PROGRAMMING 1700
4646 Block Towers brute force greedy math number theory Statement C 8VC Venture Cup 2016 - Elimination Round {626} PROGRAMMING 23522 1600
12953 Divisibility math number theory Statement J Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1200
6534 Indivisibility math number theory Statement K Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1700
4751 Longest Subsequence brute force math number theory Statement D Educational Codeforces Round 9 {632} PROGRAMMING 43493 2200
15052 Ebony and Ivory brute force math number theory Statement A Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 1200
7334 A Trivial Problem brute force constructive algorithms math number theory Statement B Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 1300
982 Yash And Trees bitmasks data structures dfs and similar math number theory Statement G Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 2700
1606 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
1046 Cowslip Collections combinatorics math number theory Statement F CROC 2016 - Elimination Round {645} PROGRAMMING Editorial for CROC 2016 Elimination Round 2500
812 Move by Prime combinatorics math number theory Statement G IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} PROGRAMMING IndiaHacks Finals 2016 — Editorial 3000
10703 Co-prime Array greedy implementation math number theory Statement A Educational Codeforces Round 11 {660} PROGRAMMING Editorial of Educational Codeforces Round 11 1300
22448 Complicated GCD math number theory Statement A Codeforces Round 347 (Div. 2) {664} PROGRAMMING Editorial for CROC 2016 Finals and Codeforces Round #347 900
841 Four Divisors dp math number theory Statement F Educational Codeforces Round 12 {665} PROGRAMMING Editorial 2600
11286 Joty and Chocolate implementation math number theory Statement C Educational Codeforces Round 13 {678} PROGRAMMING Editorial 1600
5538 Iterated Linear Function math number theory Statement D Educational Codeforces Round 13 {678} PROGRAMMING Editorial 1800
24384 Alyona and Numbers constructive algorithms math number theory Statement A Codeforces Round 358 (Div. 2) {682} PROGRAMMING 45491 1200
7125 Remainders Game chinese remainder theorem math number theory Statement B Codeforces Round 360 (Div. 1) {687} PROGRAMMING Codeforces Round #360 Editorial [+ Challenges!] 1900
13640 Pythagorean Triples math number theory Statement C Codeforces Round 368 (Div. 2) {707} PROGRAMMING 46662 1500
1441 ZS and The Birthday Paradox math number theory probabilities Statement E Codeforces Round 369 (Div. 2) {711} PROGRAMMING 46830 2400
507 Festival Organization math number theory Statement A Bubble Cup 9 - Finals [Online Mirror] {717} PROGRAMMING Tutorial 3000
2297 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
1613 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
3201 Video Cards brute force data structures implementation math number theory Statement F Codeforces Round 376 (Div. 2) {731} PROGRAMMING 47840 1900
16337 Taxes math number theory Statement D Codeforces Round 382 (Div. 2) {735} PROGRAMMING Codeforces Round #382 Editorial 1600
53908 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
10163 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
13610 Vladik and fractions brute force constructive algorithms math number theory Statement C Codeforces Round 384 (Div. 2) {743} PROGRAMMING Codeforces Round #384 Editorial 1500
58382 Bachgold Problem greedy implementation math number theory Statement A Codeforces Round 388 (Div. 2) {749} PROGRAMMING Tutorial 700
1154 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
20258 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
270 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
11636 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
762 Geometrical Progression brute force math number theory Statement F Codeforces Round 392 (Div. 2) {758} PROGRAMMING Codeforces Round #392 (Div. 2) Editorial 2500
27168 k-th divisor math number theory Statement A Educational Codeforces Round 17 {762} PROGRAMMING Tutorial 1500
820 Timofey and remoduling brute force implementation math number theory Statement C Codeforces Round 395 (Div. 1) {763} PROGRAMMING Codeforces Round #395 [Editorial] 2500
120 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
39120 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
1158 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
1498 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
396 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
282 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
2541 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
3992 Anton and School - 2 combinatorics dp math number theory Statement D Codeforces Round 404 (Div. 2) {785} PROGRAMMING Editorial 2200
12286 The Monster brute force math number theory Statement A Codeforces Round 406 (Div. 2) {787} PROGRAMMING Codeforces Round #406 Editorial 1300
5131 Divide by Three dp greedy math number theory Statement C Educational Codeforces Round 18 {792} PROGRAMMING Educational Codeforces Round 18 - Editorial 2000
1305 Colored Balls greedy math number theory Statement E Educational Codeforces Round 18 {792} PROGRAMMING Educational Codeforces Round 18 - Editorial 2400
20752 k-Factorization implementation math number theory Statement A Educational Codeforces Round 19 {797} PROGRAMMING 51588 1100
1010 Surprise me! divide and conquer math number theory trees Statement E Codeforces Round 415 (Div. 1) {809} PROGRAMMING 52099 3000
6979 Treasure Hunt implementation math number theory Statement A Educational Codeforces Round 23 {817} PROGRAMMING 52638 1200
3312 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
37635 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
1393 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
6630 The Meaningless Game math number theory Statement A Codeforces Round 426 (Div. 1) {833} PROGRAMMING Codeforces Round #426 Editorial 1700
1204 Airplane Arrangements math number theory Statement D IndiaHacks 2nd Elimination 2017 (unofficial, unrated mirror, ICPC rules) {838} PROGRAMMING 53736 2700
3727 Winter is here combinatorics dp math number theory Statement D Codeforces Round 428 (Div. 2) {839} PROGRAMMING Codeforces Round #428 editorial 2200
7607 Leha and Function combinatorics greedy math number theory sortings Statement A Codeforces Round 429 (Div. 1) {840} PROGRAMMING Editorial 1300
3830 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
671 Product transformation combinatorics math number theory Statement F Bubble Cup X - Finals [Online Mirror] {852} PROGRAMMING Tutorial 2300
9421 k-rounding brute force math number theory Statement A Технокубок 2018 - Отборочный Раунд 1 {858} PROGRAMMING Codeforces Round 434 Div.1+Div.2 (and Technocup 2018 — Elimination Round 1) Editorial 1200
9849 Maximum splitting dp greedy math number theory Statement C Technocup 2018 - Elimination Round 2 {870} PROGRAMMING Editorial Codeforces Round 440 Div.1+Div.2 (and Technocup 2018 — Elimination Round 2) 1300
10511 Divisiblity of Differences implementation math number theory Statement B Codeforces Round 441 (Div. 2, by Moscow Team Olympiad) {876} PROGRAMMING Codeforces Round #441. Editorial. 1300
15230 Pride brute force dp greedy math number theory Statement A Codeforces Round 446 (Div. 1) {891} PROGRAMMING Codeforces Round #446 Editorial 1600
4357 Counting Arrays combinatorics dp math number theory Statement E Educational Codeforces Round 33 (Rated for Div. 2) {893} PROGRAMMING 55989 2000
4731 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
770 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
8479 Position in Fraction math number theory Statement B Codeforces Round 450 (Div. 2) {900} PROGRAMMING Codeforces Round #450(Div. 2). Editorial. 1300
3980 Unusual Sequences bitmasks combinatorics dp math number theory Statement D Codeforces Round 450 (Div. 2) {900} PROGRAMMING Codeforces Round #450(Div. 2). Editorial. 2100
2858 Power Tower chinese remainder theorem math number theory Statement D Codeforces Round 454 (Div. 1, based on Technocup 2018 Elimination Round 4) {906} PROGRAMMING Editorial Codeforces Round 454 (and Technocup 2018 — Elimination Round 4) 2600
2256 Prime Gift binary search dfs and similar math meet-in-the-middle number theory two pointers Statement E Codeforces Round 456 (Div. 2) {912} PROGRAMMING Codeforces Round #456 (Div. 2) Editorial 2600
299 Power Substring math number theory Statement G Hello 2018 {913} PROGRAMMING Tutorial 3100
1543 Coprime Arrays math number theory Statement G Educational Codeforces Round 36 (Rated for Div. 2) {915} PROGRAMMING 57123 2500
2575 Congruence Equation chinese remainder theorem math number theory Statement E Codeforces Round 460 (Div. 2) {919} PROGRAMMING Codeforces Round #460 (Div. 2) Editorial 2100
2074 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
5483 Primal Sport math number theory Statement A VK Cup 2018 - Round 1 {923} PROGRAMMING VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial 1700
7316 Vile Grasshoppers brute force math number theory Statement B Codeforces Round 467 (Div. 2) {937} PROGRAMMING Codeforces Round #467, Editorial 1500
11551 Weird Subtraction Process math number theory Statement B Educational Codeforces Round 39 (Rated for Div. 2) {946} PROGRAMMING 58210 1200
2948 Sad powers binary search math number theory Statement C Codeforces Round 471 (Div. 2) {955} PROGRAMMING Editorial 2100
3320 Mahmoud and Ehab and another array construction task constructive algorithms greedy math number theory Statement D Codeforces Round 473 (Div. 2) {959} PROGRAMMING Codeforces round #473 editorial 2000
1829 Partitions combinatorics math number theory Statement G Educational Codeforces Round 41 (Rated for Div. 2) {961} PROGRAMMING Educational Codeforces Round 41 Editorial 2700
3674 Alternating Sum math number theory Statement A Tinkoff Internship Warmup Round 2018 and Codeforces Round 475 (Div. 1) {963} PROGRAMMING Editorial Tinkoff Internship Warmup Round 2018 and Codeforces Round #475 (Div. 1 + Div. 2) 1800
707 Cutting Rectangle brute force math number theory Statement C Tinkoff Internship Warmup Round 2018 and Codeforces Round 475 (Div. 1) {963} PROGRAMMING Editorial Tinkoff Internship Warmup Round 2018 and Codeforces Round #475 (Div. 1 + Div. 2) 2600
2271 Kuro and GCD and XOR and SUM binary search bitmasks brute force data structures dp dsu greedy math number theory strings trees Statement D Codeforces Round 482 (Div. 2) {979} PROGRAMMING 1750.0 Codeforces Round #482 (Div. 2) Editorial 2200
3104 Perfect Groups dp math number theory Statement D Codeforces Round 480 (Div. 2) {980} PROGRAMMING Tutorial 2100
970 Prince's Problem brute force data structures math number theory trees Statement E Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 2900
895 Oppa Funcan Style Remastered graphs math number theory shortest paths Statement F Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 3200
6835 Nastya Studies Informatics math number theory Statement B Codeforces Round 489 (Div. 2) {992} PROGRAMMING 60083 1700
1064 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
364 Appropriate Team bitmasks math number theory Statement G Educational Codeforces Round 48 (Rated for Div. 2) {1016} PROGRAMMING Разбор Educational Codeforces Round 48 2800
4321 Recovering BST brute force dp math number theory trees Statement D Codeforces Round 505 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1025} PROGRAMMING Codeforces Round #505 Editorial 2000
388 X-mouse in the Campus bitmasks math number theory Statement G Educational Codeforces Round 49 (Rated for Div. 2) {1027} PROGRAMMING Educational Codeforces Round 49 Editorial 2800
2893 Multicolored Markers binary search brute force math number theory Statement F Codeforces Round 506 (Div. 3) {1029} PROGRAMMING Codeforces Round #506 (Div. 3) Editorial 2100
12349 Square Difference math number theory Statement B Lyft Level 5 Challenge 2018 - Elimination Round {1033} PROGRAMMING The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial 1100
2667 Divisors interactive math number theory Statement D Lyft Level 5 Challenge 2018 - Elimination Round {1033} PROGRAMMING The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial 2000
1910 Relatively Prime Powers combinatorics math number theory Statement F Educational Codeforces Round 50 (Rated for Div. 2) {1036} PROGRAMMING 61727 2400
3211 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
19107 Relatively Prime Pairs greedy math number theory Statement B Educational Codeforces Round 51 (Rated for Div. 2) {1051} PROGRAMMING Educational Codeforces Round 51 Editorial 1000
333 Epic Convolution chinese remainder theorem fft math number theory Statement H Mail.Ru Cup 2018 Round 1 {1054} PROGRAMMING Editorial 3400
2092 Lucky Days math number theory Statement C Mail.Ru Cup 2018 Round 2 {1055} PROGRAMMING Mail.Ru Cup 2018 Round 2 — analysis 1900
4572 Divide Candies math number theory Statement B Mail.Ru Cup 2018 Round 3 {1056} PROGRAMMING Mail.Ru Cup 2018 Round 3 Editorial 1600
11194 Multiplicity data structures dp implementation math number theory Statement C Codeforces Round 523 (Div. 2) {1061} PROGRAMMING Tutorial (en) 1700
10211 Math greedy math number theory Statement B Codeforces Round 520 (Div. 2) {1062} PROGRAMMING Tutorial 1600
13345 LCM math number theory Statement B Codeforces Round 518 (Div. 2) [Thanks, Mail.Ru!] {1068} PROGRAMMING E 1200
14874 Divisor Subtraction implementation math number theory Statement B Educational Codeforces Round 54 (Rated for Div. 2) {1076} PROGRAMMING E 1200
2849 Missing Numbers binary search constructive algorithms greedy math number theory Statement E Avito Cool Challenge 2018 {1081} PROGRAMMING 63888 1900
10640 New Year and the Sphere Transmission math number theory Statement C Good Bye 2018 {1091} PROGRAMMING Editorial 1400
257 New Year and the Factorisation Collaboration interactive math number theory Statement G Good Bye 2018 {1091} PROGRAMMING Editorial 3100
3345 Makoto and a Blackboard dp math number theory probabilities Statement D Hello 2019 {1097} PROGRAMMING 64310 2200
449 Fedya the Potter binary search implementation math number theory Statement E Codeforces Round 530 (Div. 1) {1098} PROGRAMMING 64331 3400
417 Radix sum fft math number theory Statement E Codeforces Round 534 (Div. 1) {1103} PROGRAMMING Codeforces Round #534 — Editorial 3300
1254 Lunar New Year and a Recursive Sequence math matrices number theory Statement F Codeforces Round 536 (Div. 2) {1106} PROGRAMMING Tutorial 2400
18012 Digital root math number theory Statement B Educational Codeforces Round 59 (Rated for Div. 2) {1107} PROGRAMMING Educational Codeforces Round 59 Editorial 1100
3937 Compression dp implementation math number theory Statement D Educational Codeforces Round 59 (Rated for Div. 2) {1107} PROGRAMMING Educational Codeforces Round 59 Editorial 1800
25530 Divisors of Two Integers brute force greedy math number theory Statement B Codeforces Round 535 (Div. 3) {1108} PROGRAMMING 64751 1100
1555 Sasha and Interesting Fact from Graph Theory brute force combinatorics dp math trees Statement D Codeforces Round 539 (Div. 1) {1109} PROGRAMMING Codeforces Round #539 Editorial 2600
663 Sasha and a Very Easy Test data structures number theory Statement E Codeforces Round 539 (Div. 1) {1109} PROGRAMMING Codeforces Round #539 Editorial 2700
10122 Meaningless Operations constructive algorithms math number theory Statement C Codeforces Global Round 1 {1110} PROGRAMMING The Editorial of the First Codeforces Global Round 1500
8063 Trailing Loves (or L'oeufs?) brute force implementation math number theory Statement C Codeforces Round 538 (Div. 2) {1114} PROGRAMMING Codeforces Round #538 (Div. 2) Editorial 1700
2610 Please, another Queries on Array? bitmasks data structures divide and conquer math number theory Statement F Codeforces Round 538 (Div. 2) {1114} PROGRAMMING Codeforces Round #538 (Div. 2) Editorial 2500
14566 Preparation for International Women's Day math number theory Statement B Codeforces Round 544 (Div. 3) {1133} PROGRAMMING Codeforces Round #544 (Div. 3) Editorial 1300
17572 Zero Quantity Maximization hashing math number theory Statement D Codeforces Round 544 (Div. 3) {1133} PROGRAMMING Codeforces Round #544 (Div. 3) Editorial 1500
2845 Steps to One dp math number theory probabilities Statement D Codeforces Round 548 (Div. 2) {1139} PROGRAMMING Codeforces Round #548 Editorial 2300
11769 Nirvana brute force math number theory Statement B Codeforces Round 549 (Div. 2) {1143} PROGRAMMING Codeforces Round #549 Editorial 1300
4486 Median String bitmasks math number theory strings Statement E Codeforces Round 550 (Div. 3) {1144} PROGRAMMING 66307 1900
1232 Frog Jumping dfs and similar math number theory Statement D Forethought Future Cup - Elimination Round {1146} PROGRAMMING 66639 2100
664 Gold Experience constructive algorithms graphs math number theory probabilities Statement G Codeforces Global Round 3 {1148} PROGRAMMING Codeforces Global Round 3 Editorial 3100
18255 Prefix Sum Primes constructive algorithms greedy math number theory Statement A Codeforces Round 556 (Div. 1) {1149} PROGRAMMING 66783 1300
7165 Neko does Maths brute force math number theory Statement C Codeforces Round 554 (Div. 2) {1152} PROGRAMMING T 1800
3415 Minimum Possible LCM brute force greedy math number theory Statement G Codeforces Round 552 (Div. 3) {1154} PROGRAMMING Codeforces Round #552 (Div. 3) Editorial 2400
9847 Alarm Clocks Everywhere math number theory Statement C Educational Codeforces Round 63 (Rated for Div. 2) {1155} PROGRAMMING 66687 1300
20384 Almost All Divisors math number theory Statement D Codeforces Round 560 (Div. 3) {1165} PROGRAMMING Codeforces Round #560 (Div. 3) Editorial 1600
11992 All the Vowels Please constructive algorithms math number theory Statement B Codeforces Round 561 (Div. 2) {1166} PROGRAMMING Codeforces Round #561 (Div. 2) Editorial 1100
3046 The LCMs Must be Large bitmasks brute force constructive algorithms math number theory Statement E Codeforces Round 561 (Div. 2) {1166} PROGRAMMING Codeforces Round #561 (Div. 2) Editorial 2000
1853 Ehab and the Expected GCD Problem combinatorics dp math number theory Statement E Codeforces Round 563 (Div. 2) {1174} PROGRAMMING Codeforces round #563 editorial 2500
7979 Prime Graph constructive algorithms greedy math number theory Statement D Codeforces Global Round 4 {1178} PROGRAMMING E 1600
3490 Product Oriented Recurrence dp math matrices number theory Statement E Codeforces Round 566 (Div. 2) {1182} PROGRAMMING 67614 2200
6668 Heidi Learns Hashing (Easy) brute force math number theory Statement A1 Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} PROGRAMMING helvetic-coding-contest-2019-editorial.pdf 1200
177 Heidi Learns Hashing (Hard) fft math number theory Statement A3 Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} PROGRAMMING helvetic-coding-contest-2019-editorial.pdf 3100
5423 Count Pairs math matrices number theory two pointers Statement B Codeforces Round 572 (Div. 1) {1188} PROGRAMMING Editorial of Codeforces Round #572 2200
8246 Submarine in the Rybinsk Sea (easy edition) combinatorics math number theory Statement D1 Codeforces Round 574 (Div. 2) {1195} PROGRAMMING Разбор Codeforces Round #574 (Div. 2) 1500
4928 Submarine in the Rybinsk Sea (hard edition) combinatorics math number theory Statement D2 Codeforces Round 574 (Div. 2) {1195} PROGRAMMING Разбор Codeforces Round #574 (Div. 2) 1700
10714 Round Corridor math number theory Statement C Codeforces Round 578 (Div. 2) {1200} PROGRAMMING Codeforces Round #578 (Div. 2) Editorial 1500
1244 Graph Traveler brute force data structures dfs and similar dp graphs implementation math number theory Statement F Codeforces Round 578 (Div. 2) {1200} PROGRAMMING Codeforces Round #578 (Div. 2) Editorial 2500
2299 Natasha, Sasha and the Prefix Sums combinatorics dp math number theory Statement E Codeforces Round 581 (Div. 2) {1204} PROGRAMMING 69244 2400
983 Polygons greedy math number theory Statement G Manthan, Codefest 19 (open for everyone, rated, Div. 1 + Div. 2) {1208} PROGRAMMING 69357 2700
8601 Koala and Lights implementation math number theory Statement B Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} PROGRAMMING 69791 1300
3669 Kamil and Making a Stream math number theory trees Statement C Dasha Code Championship - SPb Finals Round (only for onsite-finalists) {1210} PROGRAMMING Dasha Code Championship Finals and Mirror Round 588 Editorial 2100
89 King's Path *special math trees Statement G Kotlin Heroes: Episode 2 {1211} PROGRAMMING Kotlin Heroes: Episode 2 Editorial 2500
12203 Multiplication Table math number theory Statement B Codeforces Round 586 (Div. 1 + Div. 2) {1220} PROGRAMMING Codeforces Round #586 Editorial 1300
4153 Alex and Julian bitmasks math number theory Statement D Codeforces Round 586 (Div. 1 + Div. 2) {1220} PROGRAMMING Codeforces Round #586 Editorial 1900
431 Wooden Raft binary search math number theory Statement G Technocup 2020 - Elimination Round 1 {1223} PROGRAMMING Сodeforces Round 591 (and Technocup 2020 — Elimination Round 1) Editorial 3100
10563 Power Products hashing math number theory Statement D Technocup 2020 - Elimination Round 2 {1225} PROGRAMMING 70898 1900
9788 Primes and Multiplication math number theory Statement C Codeforces Round 589 (Div. 2) {1228} PROGRAMMING 70162 1600
28659 Prime Subtraction math number theory Statement A Educational Codeforces Round 74 (Rated for Div. 2) {1238} PROGRAMMING Educational Codeforces Round 74 Editorial 900
13344 Tile Painting constructive algorithms math number theory Statement A Codeforces Round 599 (Div. 1) {1242} PROGRAMMING Codeforces Round #599 Editorial 1500
8487 The Football Season brute force math number theory Statement C Codeforces Round 592 (Div. 2) {1244} PROGRAMMING Codeforces Round #592 (Div. 2) Tutorial 1900
15008 Good ol' Numbers Coloring math number theory Statement A Codeforces Round 597 (Div. 2) {1245} PROGRAMMING Codeforces Round #597 (Div. 2) Editorial 1000
5099 Send Boxes to Alice (Easy Version) constructive algorithms greedy math number theory ternary search two pointers Statement B1 Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 2000
3574 Send Boxes to Alice (Hard Version) constructive algorithms greedy math number theory ternary search two pointers Statement B2 Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 2100
806 Divisor Set divide and conquer fft greedy math number theory Statement G Educational Codeforces Round 76 (Rated for Div. 2) {1257} PROGRAMMING Educational Codeforces Round 76 Editorial 2700
8960 Infinite Fence greedy math number theory Statement C Educational Codeforces Round 77 (Rated for Div. 2) {1260} PROGRAMMING Educational Codeforces Round 77 Editorial 1700
14825 Everyone is a Winner! binary search math meet-in-the-middle number theory Statement C Codeforces Round 603 (Div. 2) {1263} PROGRAMMING Разбор Codeforces Round #603 (Div. 2) 1400
10122 Diverse Matrix constructive algorithms greedy math number theory Statement C Codeforces Global Round 6 {1266} PROGRAMMING Codeforces Global Round 6 Editorial 1400
2894 Cards combinatorics dp math number theory probabilities Statement F Educational Codeforces Round 78 (Rated for Div. 2) {1278} PROGRAMMING Educational Codeforces Round 78 Editorial 2600
29077 Fadi and LCM brute force math number theory Statement C Codeforces Round 613 (Div. 2) {1285} PROGRAMMING Codeforces Round #613 (Div. 2) Editorial 1400
1069 Chaotic V. dp graphs greedy math number theory trees Statement D Codeforces Round 614 (Div. 1) {1292} PROGRAMMING 1750.0 Codeforces Round #614 Editorial 2700
49311 Product of Three Numbers greedy math number theory Statement C Codeforces Round 615 (Div. 3) {1294} PROGRAMMING Codeforces Round #615 (Div. 3) Editorial 1300
10606 Same GCDs math number theory Statement D Educational Codeforces Round 81 (Rated for Div. 2) {1295} PROGRAMMING Educational Codeforces Round 81 Editorial 1800