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1 2 3 >Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 18288 | Longest Regular Bracket Sequence | constructive algorithms data structures dp greedy sortings strings | Statement | C | Codeforces Beta Round 5 {5} | PROGRAMMING | C, D и E с CBR5 - разбор | 1900 | |
| 15600 | Increasing Sequence | constructive algorithms implementation math | Statement | A | Codeforces Beta Round 11 {11} | PROGRAMMING | 1100 | ||
| 3871 | Four Segments | brute force constructive algorithms geometry implementation math | Statement | C | Codeforces Beta Round 14 (Div. 2) {14} | PROGRAMMING | Codeforces Beta Round #14 tutorial | 1800 | |
| 3895 | Party | constructive algorithms graphs math | Statement | B | Codeforces Beta Round 23 {23} | PROGRAMMING | Codeforces Beta Round #23 tutorial | 1600 | |
| 4452 | Find Color | constructive algorithms geometry implementation math | Statement | A | Codeforces Beta Round 39 {40} | PROGRAMMING | codeforces #39 | 1300 | |
| 490 | Strange town | constructive algorithms math | Statement | D | Codeforces Beta Round 41 {42} | PROGRAMMING | Solution of task е, Codeforces beta round #41 | 2300 | |
| 1875 | Disposition | constructive algorithms math | Statement | C | Codeforces Beta Round 46 (Div. 2) {49} | PROGRAMMING | 1700 | ||
| 3737 | 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 | |
| 454 | Tetris revisited | constructive algorithms graph matchings greedy math | Statement | B | Yandex.Algorithm 2011: Round 2 {86} | PROGRAMMING | Problemset analysis (Yandex, Round 2) | 2100 | |
| 1140 | Before Exam | constructive algorithms implementation sortings | Statement | B | Codeforces Beta Round 90 {119} | PROGRAMMING | Разбор задачи E Codeforces Beta Round #90 | 1700 | |
| 113199 | Insomnia cure | constructive algorithms implementation math | Statement | A | Codeforces Round 105 (Div. 2) {148} | PROGRAMMING | Codeforces Round #105 (Div. 2): editorial | 900 | |
| 2857 | Mathematical Analysis Rocks! | constructive algorithms implementation math | Statement | F | Codeforces Round 116 (Div. 2, ACM-ICPC Rules) {180} | PROGRAMMING | 1300 | ||
| 668 | Headquarters | constructive algorithms math | Statement | A | Croc Champ 2012 - Final {183} | PROGRAMMING | CROC Champ 2012 — Round 3 (Editorial) | 1900 | |
| 618 | Hamming Distance | constructive algorithms greedy math matrices | Statement | C | Codeforces Round 122 (Div. 1) {193} | PROGRAMMING | Editoral Codeforces Round #122 | 2400 | |
| 6864 | Plate Game | constructive algorithms games math | Statement | A | Codeforces Round 124 (Div. 2) {197} | PROGRAMMING | Разбор задач | 1600 | |
| 3252 | Clear Symmetry | constructive algorithms dp math | Statement | A | Codeforces Round 127 (Div. 1) {201} | PROGRAMMING | Разбор задач | 1700 | |
| 488 | Pixels | constructive algorithms math | Statement | B | VK Cup 2012 Finals, Practice Session {209} | PROGRAMMING | 2200 | ||
| 5367 | Hometask | brute force constructive algorithms greedy math | Statement | B | Codeforces Round 131 (Div. 2) {214} | PROGRAMMING | Codeforces Round #131 Tutorial | 1600 | |
| 3932 | Magic, Wizardry and Wonders | constructive algorithms greedy | Statement | B | Codeforces Round 143 (Div. 2) {231} | PROGRAMMING | Tutorial Codeforces Round #143 | 1600 | |
| 311 | Doe Graphs | constructive algorithms divide and conquer dp graphs shortest paths | Statement | C | Codeforces Round 144 (Div. 1) {232} | PROGRAMMING | Editorial for Codeforces Round #144 | 2700 | |
| 2187 | Not Wool Sequences | constructive algorithms math | Statement | A | Codeforces Round 148 (Div. 1) {238} | PROGRAMMING | Editorial for Codeforces Round #148 | 1700 | |
| 841 | Maxim and Matrix | constructive algorithms dp math | Statement | C | Codeforces Round 160 (Div. 1) {261} | PROGRAMMING | Codeforces Round #160 tutorial | 2300 | |
| 1435 | Below the Diagonal | constructive algorithms greedy math | Statement | C | Codeforces Round 163 (Div. 2) {266} | PROGRAMMING | Codeforces Round #163 (Div. 2) Tutorial | 2000 | |
| 14684 | Beautiful Sets of Points | constructive algorithms implementation | Statement | C | Codeforces Round 164 (Div. 2) {268} | PROGRAMMING | Codeforces Round #164 (Div. 2) — Разбор задач | 1500 | |
| 601 | Three Horses | constructive algorithms math number theory | Statement | E | Codeforces Round 166 (Div. 2) {271} | PROGRAMMING | 6662 | 2500 | |
| 10228 | XOR and OR | constructive algorithms implementation math | Statement | C | Codeforces Round 173 (Div. 2) {282} | PROGRAMMING | Round #173 — Editorial | 1600 | |
| 3460 | Lucky Permutation | constructive algorithms math | Statement | A | Codeforces Round 176 (Div. 1) {286} | PROGRAMMING | Tutorial | 1600 | |
| 1022 | Ladies' Shop | constructive algorithms fft math | Statement | E | Codeforces Round 176 (Div. 1) {286} | PROGRAMMING | Tutorial | 2600 | |
| 8592 | Lucky Permutation Triple | constructive algorithms implementation math | Statement | A | Codeforces Round 183 (Div. 1) {303} | PROGRAMMING | Codeforces Round #183 Editorial | 1400 | |
| 5960 | Ilya and Matrix | constructive algorithms greedy implementation sortings | Statement | C | Codeforces Round 186 (Div. 2) {313} | PROGRAMMING | Tutorial | 1400 | |
| 2440 | Two Heaps | combinatorics constructive algorithms greedy implementation math sortings | Statement | B | Codeforces Round 205 (Div. 2) {353} | PROGRAMMING | 9145 | 1800 | |
| 8729 | Permutation | constructive algorithms dp math | Statement | B | Codeforces Round 209 (Div. 2) {359} | PROGRAMMING | Editorial Codeforces Round #209 (Div. 2) | 1400 | |
| 8810 | Levko and Permutation | constructive algorithms math number theory | Statement | B | Codeforces Round 210 (Div. 2) {361} | PROGRAMMING | Codeforces Round #210 editorial | 1200 | |
| 6883 | Valera and Contest | constructive algorithms implementation math | Statement | B | Codeforces Round 216 (Div. 2) {369} | PROGRAMMING | Editorial Codeforces Round #216 (Div. 2) | 1500 | |
| 1725 | Mittens | constructive algorithms greedy sortings | Statement | C | Codeforces Round 217 (Div. 2) {370} | PROGRAMMING | Codeforces Round #217 (Div. 2): tutorial | 1800 | |
| 2604 | Fox and Minimal path | bitmasks constructive algorithms graphs implementation math | Statement | B | Codeforces Round 228 (Div. 1) {388} | PROGRAMMING | Codeforces Round #228 — Editorial | 2000 | |
| 835 | On Corruption and Numbers | constructive algorithms implementation math | Statement | B | Codeforces Round 232 (Div. 2) {397} | PROGRAMMING | 1000.0 | Codeforces Round #232 Editorial (restored) | |
| 932 | Square Table | constructive algorithms math probabilities | Statement | E | RCC 2014 Warmup (Div. 2) {417} | PROGRAMMING | RCC 2014 WarmUp Analysis | 2400 | |
| 1202 | Valera and Swaps | constructive algorithms dsu graphs implementation math string suffix structures | Statement | D | Codeforces Round 252 (Div. 2) {441} | PROGRAMMING | Разбор Codeforces Round #252 (Div. 2) | 2300 | |
| 121 | Flow Optimality | constructive algorithms flows math | Statement | E | MemSQL Start[c]UP 2.0 - Round 2 {457} | PROGRAMMING | MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials | 3200 | |
| 6493 | Pashmak and Buses | combinatorics constructive algorithms math | Statement | C | Codeforces Round 261 (Div. 2) {459} | PROGRAMMING | Codeforces Round #261 Editorial | 1900 | |
| 1039 | Little Victor and Set | brute force constructive algorithms math | Statement | D | Codeforces Round 262 (Div. 2) {460} | PROGRAMMING | 13465 | 2500 | |
| 8410 | 24 Game | constructive algorithms greedy math | Statement | A | Codeforces Round 268 (Div. 1) {468} | PROGRAMMING | 13896 | 1600 | |
| 2744 | Hack it! | binary search constructive algorithms math | Statement | C | Codeforces Round 268 (Div. 1) {468} | PROGRAMMING | 13896 | 2800 | |
| 301 | Design Tutorial: Change the Goal | constructive algorithms math matrices | Statement | F | Codeforces Round 270 {472} | PROGRAMMING | 2600 | ||
| 5042 | Dreamoon and Sets | constructive algorithms greedy math | Statement | D | Codeforces Round 272 (Div. 2) {476} | PROGRAMMING | Editorial | 2000 | |
| 41446 | Random Teams | combinatorics constructive algorithms greedy math | Statement | B | Codeforces Round 273 (Div. 2) {478} | PROGRAMMING | Editorial | 1300 | |
| 3090 | Prefix Product Sequence | constructive algorithms math number theory | Statement | C | Codeforces Round 278 (Div. 1) {487} | PROGRAMMING | Tutorial | 2600 | |
| 2263 | Candy Boxes | brute force constructive algorithms math | Statement | B | Codeforces Round 278 (Div. 2) {488} | PROGRAMMING | Tutorial | 1800 | |
| 10234 | Vasya and Chess | constructive algorithms games math | Statement | D | Codeforces Round 281 (Div. 2) {493} | PROGRAMMING | Codeforces Round #281 (Div. 2) Editorial | 1700 | |
| 6042 | New Year Book Reading | constructive algorithms greedy implementation math | Statement | C | Good Bye 2014 {500} | PROGRAMMING | Tutorial 2 | 1600 | |
| 815 | Restoring Numbers | constructive algorithms math | Statement | D | Codeforces Round 289 (Div. 2, ACM ICPC Rules) {509} | PROGRAMMING | Tutorial CodeForces Round 289 (Div.2) (Second Winter Computer Camp Selection 2015) | 2400 | |
| 21878 | Game | constructive algorithms math | Statement | A | Rockethon 2015 {513} | PROGRAMMING | 16260 | 900 | |
| 10278 | Pasha and String | constructive algorithms greedy math strings | Statement | B | Codeforces Round 297 (Div. 2) {525} | PROGRAMMING | Codeforces Round #297 (Div.2) Editorial | 1500 | |
| 12945 | Exam | constructive algorithms implementation math | Statement | A | Codeforces Round 298 (Div. 2) {534} | PROGRAMMING | 1100 | ||
| 578 | Berserk Robot | constructive algorithms math sortings | Statement | G | Codeforces Round 300 {538} | PROGRAMMING | Codeforces Round #300 Editorial (+challenges) | 3100 | |
| 1267 | Idempotent functions | constructive algorithms graphs math | Statement | C | VK Cup 2015 - Round 3 (unofficial online mirror, Div. 1 only) {542} | PROGRAMMING | 17697 | 2000 | |
| 13844 | 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 | |
| 1500 | Brackets in Implications | constructive algorithms greedy implementation math | Statement | E | Codeforces Round 306 (Div. 2) {550} | PROGRAMMING | Codeforces Round #306 (Div. 2) Editorial | 2300 | |
| 2272 | 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 | |
| 7491 | Pasha and Tea | constructive algorithms implementation math sortings | Statement | B | Codeforces Round 311 (Div. 2) {557} | PROGRAMMING | Codeforces Round #311 (Div.2) Editorial | 1500 | |
| 16906 | Simple Game | constructive algorithms games greedy implementation math | Statement | B | Codeforces Round 316 (Div. 2) {570} | PROGRAMMING | Codeforces Round #316 Editorial | 1300 | |
| 4762 | Three Logos | bitmasks brute force constructive algorithms geometry implementation math | Statement | D | Codeforces Round 322 (Div. 2) {581} | PROGRAMMING | Codeforces Round #322 (Div.2) Editorial | 1700 | |
| 1497 | Anton and Ira | constructive algorithms greedy math | Statement | E | Codeforces Round 324 (Div. 2) {584} | PROGRAMMING | Tutorial | 2400 | |
| 325 | Beautiful Function | constructive algorithms math | Statement | C | Codeforces Round 329 (Div. 2) {593} | PROGRAMMING | 2700 | ||
| 2017 | Square Root of Permutation | combinatorics constructive algorithms dfs and similar graphs math | Statement | E | Educational Codeforces Round 4 {612} | PROGRAMMING | 22299 | 2200 | |
| 1083 | Necklace | constructive algorithms math | Statement | C | Codeforces Round 339 (Div. 1) {613} | PROGRAMMING | Tutorial | 2800 | |
| 1088 | Rat Kwesh and Cheese | brute force constructive algorithms math | Statement | D | Codeforces Round 341 (Div. 2) {621} | PROGRAMMING | Editorial | 2200 | |
| 7175 | K-special Tables | constructive algorithms implementation | Statement | C | Codeforces Round 342 (Div. 2) {625} | PROGRAMMING | Codeforces Round #342 (Div. 2) : editorial | 1300 | |
| 679 | Finals in arithmetic | constructive algorithms implementation math | Statement | D | Codeforces Round 342 (Div. 2) {625} | PROGRAMMING | Codeforces Round #342 (Div. 2) : editorial | 2400 | |
| 6941 | Cards | constructive algorithms dp math | Statement | B | 8VC Venture Cup 2016 - Elimination Round {626} | PROGRAMMING | 23522 | 1300 | |
| 7261 | A Trivial Problem | brute force constructive algorithms math number theory | Statement | B | Manthan, Codefest 16 {633} | PROGRAMMING | Manthan, Codefest 16: Editorials | 1300 | |
| 4388 | Home Numbers | *special constructive algorithms math | Statement | A | VK Cup 2016 - Qualification Round 2 {638} | PROGRAMMING | 1500 | ||
| 656 | Ants on a Circle | constructive algorithms math | Statement | F | Educational Codeforces Round 10 {652} | PROGRAMMING | Editorial of Educational Codeforces Round 10 | 2800 | |
| 1716 | International Olympiad | constructive algorithms greedy implementation math | Statement | D | CROC 2016 - Final Round [Private, For Onsite Finalists Only] {662} | PROGRAMMING | Editorial for CROC 2016 Finals and Codeforces Round #347 | 2000 | |
| 3795 | Rebus | constructive algorithms expression parsing greedy math | Statement | A | Codeforces Round 347 (Div. 1) {663} | PROGRAMMING | Editorial for CROC 2016 Finals and Codeforces Round #347 | 1800 | |
| 18702 | Holidays | brute force constructive algorithms greedy math | Statement | A | Codeforces Round 350 (Div. 2) {670} | PROGRAMMING | Codeforces Round #350 (Div.2) Editorial | 1000 | |
| 7737 | Restoring Painting | brute force constructive algorithms math | Statement | B | Codeforces Round 353 (Div. 2) {675} | PROGRAMMING | Tutorial | 1400 | |
| 15567 | Bear and Prime 100 | constructive algorithms interactive math | Statement | A | Codeforces Round 356 (Div. 1) {679} | PROGRAMMING | Codeforces Round #356 — Editorial | 1400 | |
| 24061 | Alyona and Numbers | constructive algorithms math number theory | Statement | A | Codeforces Round 358 (Div. 2) {682} | PROGRAMMING | 45491 | 1200 | |
| 36160 | Lovely Palindromes | constructive algorithms math | Statement | B | Codeforces Round 360 (Div. 2) {688} | PROGRAMMING | Codeforces Round #360 Editorial [+ Challenges!] | 1000 | |
| 3456 | Recover the String | constructive algorithms greedy implementation math | Statement | B | AIM Tech Round 3 (Div. 1) {708} | PROGRAMMING | Editorial | 1900 | |
| 5567 | Magic Odd Square | constructive algorithms math | Statement | C | Educational Codeforces Round 16 {710} | PROGRAMMING | Editorial of Educational Codeforces Round 16 | 1600 | |
| 5878 | Plus and Square Root | constructive algorithms math | Statement | A | Codeforces Round 372 (Div. 1) {715} | PROGRAMMING | Codeforces Round #372 Editorial | 1600 | |
| 2495 | Maxim and Array | constructive algorithms data structures greedy math | Statement | D | Codeforces Round 374 (Div. 2) {721} | PROGRAMMING | Codeforces Round #374 (Div. 2) Editorial | 2000 | |
| 8998 | Guess the Array | constructive algorithms interactive math | Statement | C | Technocup 2017 - Elimination Round 1 (Unofficially Open for Everyone, Rated for Div. 2) {727} | PROGRAMMING | Tutorial | 1400 | |
| 4097 | Sea Battle | constructive algorithms greedy math | Statement | D | Technocup 2017 - Elimination Round 2 {729} | PROGRAMMING | 1700 | ||
| 10194 | Sanatorium | binary search constructive algorithms greedy implementation math | Statement | C | Codeforces Round 377 (Div. 2) {732} | PROGRAMMING | Codeforces Round #377 (Div. 2) Editorial | 1300 | |
| 89524 | Buy a Shovel | brute force constructive algorithms implementation math | Statement | A | Codeforces Round 377 (Div. 2) {732} | PROGRAMMING | Codeforces Round #377 (Div. 2) Editorial | 800 | |
| 1066 | Sleep in Class | constructive algorithms data structures math two pointers | Statement | E | Codeforces Round 378 (Div. 2) {733} | PROGRAMMING | Codeforces Round #378 (Div. 2) editorial | 2500 | |
| 1404 | Anton and School | bitmasks constructive algorithms implementation math | Statement | F | Codeforces Round 379 (Div. 2) {734} | PROGRAMMING | Tutorial of Codeforces Round #379 (Div. 2) | 2600 | |
| 7990 | Tennis Championship | combinatorics constructive algorithms greedy math | Statement | C | Codeforces Round 382 (Div. 2) {735} | PROGRAMMING | Codeforces Round #382 Editorial | 1700 | |
| 206 | Chess Championship | constructive algorithms flows greedy math | Statement | E | Codeforces Round 382 (Div. 1) {736} | PROGRAMMING | 48659 | 2800 | |
| 85 | Dirty plates | constructive algorithms math | Statement | F | Codeforces Round 380 (Div. 1, Rated, Based on Technocup 2017 - Elimination Round 2) {737} | PROGRAMMING | 3300 | ||
| 13459 | Vladik and fractions | brute force constructive algorithms math number theory | Statement | C | Codeforces Round 384 (Div. 2) {743} | PROGRAMMING | Codeforces Round #384 Editorial | 1500 | |
| 5370 | Green and Black Tea | constructive algorithms greedy math | Statement | D | Codeforces Round 386 (Div. 2) {746} | PROGRAMMING | Codeforces Round #386 (Div.2) Editorial | 1500 | |
| 3865 | Tram | constructive algorithms implementation math | Statement | C | Codeforces Round 386 (Div. 2) {746} | PROGRAMMING | Codeforces Round #386 (Div.2) Editorial | 1600 | |
| 4869 | Santa Claus and Robot | constructive algorithms math | Statement | C | Technocup 2017 - Elimination Round 3 {748} | PROGRAMMING | Codeforces Round 389 (Div.2) Editorial | 1400 | |
| 4065 | Unfair Poll | binary search constructive algorithms implementation math | Statement | C | Codeforces Round 392 (Div. 2) {758} | PROGRAMMING | Codeforces Round #392 (Div. 2) Editorial | 1700 | |
| 2940 | Ability To Convert | constructive algorithms dp greedy math strings | Statement | D | Codeforces Round 392 (Div. 2) {758} | PROGRAMMING | Codeforces Round #392 (Div. 2) Editorial | 1900 | |
| 15157 | Dasha and Stairs | brute force constructive algorithms implementation math | Statement | A | Codeforces Round 394 (Div. 2) {761} | PROGRAMMING | Codeforces Round #394 (Div. 2) [Editorial] | 1100 | |
| 2600 | Artsem and Saunders | constructive algorithms dsu math | Statement | D | Codeforces Round 397 by Kaspersky Lab and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {765} | PROGRAMMING | Codeforces Round #397 Editorial | 1700 | |
| 38523 | 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 | |
| 3509 | Mahmoud and a xor trip | bitmasks constructive algorithms data structures dfs and similar dp math trees | Statement | E | Codeforces Round 396 (Div. 2) {766} | PROGRAMMING | Codeforces round #396 editorial | 2200 | |
| 1455 | 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 | |
| 997 | Prairie Partition | binary search constructive algorithms greedy math | Statement | C | VK Cup 2017 - Round 3 {773} | PROGRAMMING | VK Cup 2017 Round 3 + Codeforces Round #412 -- Tutorial | 2300 | |
| 10916 | Shell Game | constructive algorithms implementation math | Statement | A | Codeforces Round 401 (Div. 2) {777} | PROGRAMMING | Problem analysis of Codeforces Round #401 (Div. 2) | 1100 | |
| 9713 | Pupils Redistribution | constructive algorithms math | Statement | A | Codeforces Round 402 (Div. 2) {779} | PROGRAMMING | Codeforces Round #402, Editorial | 1100 | |
| 5836 | Maximal GCD | constructive algorithms greedy math | Statement | C | Educational Codeforces Round 20 {803} | PROGRAMMING | 51768 | 2000 | |
| 16574 | Find Amir | constructive algorithms greedy math | Statement | A | Codeforces Round 411 (Div. 1) {804} | PROGRAMMING | Codeforces Round #411 Editorial | 1100 | |
| 1603 | Karen and Test | brute force combinatorics constructive algorithms math | Statement | B | Codeforces Round 419 (Div. 1) {815} | PROGRAMMING | Codeforces Round #419 Editorial | 2200 | |
| 5523 | Mister B and Angle in Polygon | constructive algorithms geometry math | Statement | B | Codeforces Round 421 (Div. 2) {820} | PROGRAMMING | Codeforces Round #421 Editorial | 1300 | |
| 338 | Perpetual Motion Machine | constructive algorithms dp graphs implementation math trees | Statement | E | Codeforces Round 424 (Div. 1, rated, based on VK Cup Finals) {830} | PROGRAMMING | Codeforces Round #424 Editorial | 3100 | |
| 408 | Upgrading Tree | constructive algorithms dfs and similar graphs math trees | Statement | C | AIM Tech Round 4 (Div. 1) {843} | PROGRAMMING | AIM Tech Round 4 -- Editorial | 2900 | |
| 469 | Tournament Construction | constructive algorithms dp graphs greedy math | Statement | D | Codeforces Round 432 (Div. 1, based on IndiaHacks Final Round 2017) {850} | PROGRAMMING | Codeforces Round #432 editorial | 2700 | |
| 8593 | Maxim Buys an Apartment | constructive algorithms math | Statement | B | Codeforces Round 433 (Div. 2, based on Olympiad of Metropolises) {854} | PROGRAMMING | 1200 | ||
| 14562 | Fraction | brute force constructive algorithms math | Statement | A | Codeforces Round 433 (Div. 2, based on Olympiad of Metropolises) {854} | PROGRAMMING | 900 | ||
| 4708 | 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 | |
| 4634 | Marco and GCD Sequence | constructive algorithms math | Statement | C | Codeforces Round 447 (Div. 2) {894} | PROGRAMMING | Codeforces Round #447 (Div.2 Only) Editorial | 1800 | |
| 9059 | Dividing the numbers | constructive algorithms graphs math | Statement | C | Codeforces Round 452 (Div. 2) {899} | PROGRAMMING | Codeforces Round #452 (Div.2) Editorial | 1300 | |
| 3268 | Shovel Sale | constructive algorithms math | Statement | D | Codeforces Round 452 (Div. 2) {899} | PROGRAMMING | Codeforces Round #452 (Div.2) Editorial | 1800 | |
| 11114 | Splitting in Teams | constructive algorithms greedy math | Statement | A | Codeforces Round 452 (Div. 2) {899} | PROGRAMMING | Codeforces Round #452 (Div.2) Editorial | 900 | |
| 1641 | GCD of Polynomials | constructive algorithms math | Statement | B | Codeforces Round 453 (Div. 1) {901} | PROGRAMMING | Codeforces Round #453 (Div. 1 & Div. 2) Editorial | 2100 | |
| 1325 | Seating of Students | brute force constructive algorithms math | Statement | B | Codeforces Round 454 (Div. 1, based on Technocup 2018 Elimination Round 4) {906} | PROGRAMMING | Editorial Codeforces Round 454 (and Technocup 2018 — Elimination Round 4) | 2300 | |
| 6777 | Segments | constructive algorithms math | Statement | B | Codeforces Round 455 (Div. 2) {909} | PROGRAMMING | Codeforces Round #455 (Div. 2) Editorial | 1300 | |
| 2170 | Minimum Sum | constructive algorithms greedy math | Statement | C | Testing Round 14 (Unrated) {910} | PROGRAMMING | 1700 | ||
| 1416 | Big Secret | constructive algorithms math | Statement | C | VK Cup 2018 - Round 3 {925} | PROGRAMMING | Разбор VK 2018 Round 3 + Codeforces Round #477 | 2200 | |
| 3838 | A Leapfrog in the Array | constructive algorithms math | Statement | B | Codeforces Round 469 (Div. 1) {949} | PROGRAMMING | 58291 | 1700 | |
| 3275 | 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 | |
| 2754 | Sand Fortress | binary search constructive algorithms math | Statement | D | Educational Codeforces Round 44 (Rated for Div. 2) {985} | PROGRAMMING | Educational Codeforces Round 44 Editorial | 2100 | |
| 9973 | Sonya and Exhibition | constructive algorithms greedy implementation math | Statement | B | Codeforces Round 495 (Div. 2) {1004} | PROGRAMMING | 60443 | 1400 | |
| 6676 | Relatively Prime Graph | brute force constructive algorithms graphs greedy math | Statement | D | Educational Codeforces Round 47 (Rated for Div. 2) {1009} | PROGRAMMING | 60630 | 1700 | |
| 4990 | Vasya And The Matrix | constructive algorithms flows math | Statement | D | Educational Codeforces Round 48 (Rated for Div. 2) {1016} | PROGRAMMING | Разбор Educational Codeforces Round 48 | 1800 | |
| 869 | Company Acquisitions | constructive algorithms math | Statement | G | Codeforces Round 505 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1025} | PROGRAMMING | Codeforces Round #505 Editorial | 3100 | |
| 10272 | Unnatural Conditions | constructive algorithms math | Statement | B | AIM Tech Round 5 (rated, Div. 1 + Div. 2) {1028} | PROGRAMMING | 61493 | 1300 | |
| 11843 | Packets | constructive algorithms greedy math | Statement | A | Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} | PROGRAMMING | Tutorial | 1300 | |
| 14760 | Non-Coprime Partition | constructive algorithms math | Statement | B | Codeforces Round 508 (Div. 2) {1038} | PROGRAMMING | Tutorial | 1100 | |
| 871 | Timetable | constructive algorithms data structures greedy math | Statement | A | Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} | PROGRAMMING | 61668 | 2400 | |
| 4976 | Array Product | constructive algorithms greedy math | Statement | C | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 1700 | |
| 3464 | Train Hard, Win Easy | constructive algorithms greedy math sortings | Statement | E | Codeforces Round 519 by Botan Investments {1043} | PROGRAMMING | Codeforces Round #519 Editorial | 1900 | |
| 514 | Chips Puzzle | constructive algorithms implementation math | Statement | E | Mail.Ru Cup 2018 Round 1 {1054} | PROGRAMMING | Editorial | 2400 | |
| 456 | New Road Network | constructive algorithms greedy math | Statement | G | Mail.Ru Cup 2018 Round 1 {1054} | PROGRAMMING | Editorial | 2900 | |
| 7552 | Sequence Transformation | constructive algorithms math | Statement | C | Codeforces Round 514 (Div. 2) {1059} | PROGRAMMING | Codeforces Round #514 (Div. 2) Editorial | 1500 | |
| 403 | Lasers and Mirrors | constructive algorithms math | Statement | E | Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} | PROGRAMMING | Editorial | 3000 | |
| 1666 | Olya and magical square | constructive algorithms implementation math | Statement | D | Codeforces Round 524 (Div. 2) {1080} | PROGRAMMING | Codeforces Round #524 (Div. 2) Editorial | 2000 | |
| 2829 | Missing Numbers | binary search constructive algorithms greedy math number theory | Statement | E | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 1900 | |
| 13294 | Definite Game | constructive algorithms math | Statement | A | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 800 | |
| 8529 | Ehab and a 2-operation task | constructive algorithms greedy math | Statement | C | Codeforces Round 525 (Div. 2) {1088} | PROGRAMMING | Codeforces round #525 editorial | 1400 | |
| 1798 | Nice table | brute force constructive algorithms greedy math | Statement | B | Codeforces Round 530 (Div. 1) {1098} | PROGRAMMING | 64331 | 2300 | |
| 11485 | Squares and Segments | binary search constructive algorithms math | Statement | B | Codeforces Round 530 (Div. 2) {1099} | PROGRAMMING | E | 1100 | |
| 958 | Johnny Solving | constructive algorithms dfs and similar graphs math | Statement | C | Codeforces Round 534 (Div. 1) {1103} | PROGRAMMING | Codeforces Round #534 — Editorial | 2800 | |
| 15915 | Splitting into digits | constructive algorithms implementation math | Statement | A | Codeforces Round 534 (Div. 2) {1104} | PROGRAMMING | Codeforces Round #534 — Editorial | 800 | |
| 10031 | Meaningless Operations | constructive algorithms math number theory | Statement | C | Codeforces Global Round 1 {1110} | PROGRAMMING | The Editorial of the First Codeforces Global Round | 1500 | |
| 4753 | Magic Stones | constructive algorithms math sortings | Statement | E | Codeforces Global Round 1 {1110} | PROGRAMMING | The Editorial of the First Codeforces Global Round | 2200 | |
| 1647 | Decypher the String | bitmasks chinese remainder theorem constructive algorithms interactive math | Statement | E | Educational Codeforces Round 60 (Rated for Div. 2) {1117} | PROGRAMMING | 65365 | 2200 | |
| 7183 | Ramesses and Corner Inversion | constructive algorithms greedy implementation math | Statement | C | Codeforces Global Round 2 {1119} | PROGRAMMING | Codeforces Global Round 2 Editorial | 1500 | |
| 480 | Once in a casino | constructive algorithms greedy implementation math | Statement | B | Codeforces Round 543 (Div. 1, based on Technocup 2019 Final Round) {1120} | PROGRAMMING | Разбор задач финала Технокубка 2019 и Codeforces Round #543 | 2700 | |
| 12284 | Nastya Is Playing Computer Games | constructive algorithms math | Statement | B | Codeforces Round 546 (Div. 2) {1136} | PROGRAMMING | Editorial of Round #546(Div.2) | 1000 | |
| 1832 | Earth Wind and Fire | constructive algorithms greedy math sortings two pointers | Statement | E | Codeforces Global Round 3 {1148} | PROGRAMMING | Codeforces Global Round 3 Editorial | 2300 | |
| 390 | Gold Experience | constructive algorithms graphs math number theory probabilities | Statement | G | Codeforces Global Round 3 {1148} | PROGRAMMING | Codeforces Global Round 3 Editorial | 3100 | |
| 17979 | Prefix Sum Primes | constructive algorithms greedy math number theory | Statement | A | Codeforces Round 556 (Div. 1) {1149} | PROGRAMMING | 66783 | 1300 | |
| 5611 | Problem for Nazar | constructive algorithms math | Statement | C | Codeforces Round 553 (Div. 2) {1151} | PROGRAMMING | Codeforces Round #553 (Div. 2) Editorial | 1700 | |
| 9355 | Neko Performs Cat Furrier Transform | bitmasks constructive algorithms dfs and similar math | Statement | B | Codeforces Round 554 (Div. 2) {1152} | PROGRAMMING | T | 1300 | |
| 4004 | N Problems During K Days | constructive algorithms greedy math | Statement | D | Codeforces Round 555 (Div. 3) {1157} | PROGRAMMING | 66737 | 2100 | |
| 8380 | The Party and Sweets | binary search constructive algorithms greedy implementation math sortings two pointers | Statement | A | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 1500 | |
| 2388 | The minimal unique substring | constructive algorithms math strings | Statement | B | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 2200 | |
| 2127 | Permutation recovery | constructive algorithms data structures dfs and similar graphs greedy math sortings | Statement | C | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 2300 | |
| 927 | Winding polygonal line | constructive algorithms geometry greedy math | Statement | D | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 2800 | |
| 1018 | Magical Permutation | bitmasks brute force constructive algorithms data structures graphs math | Statement | E | Codeforces Round 558 (Div. 2) {1163} | PROGRAMMING | 66943 | 2800 | |
| 11933 | 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 | |
| 3013 | 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 | |
| 433 | Xor Permutations | constructive algorithms math | Statement | E | Codeforces Round 562 (Div. 1) {1168} | PROGRAMMING | Codeforces Round #562 — Editorial | 3100 | |
| 7935 | Prime Graph | constructive algorithms greedy math number theory | Statement | D | Codeforces Global Round 4 {1178} | PROGRAMMING | E | 1600 | |
| 9332 | Vus the Cossack and Numbers | constructive algorithms greedy math | Statement | D | Codeforces Round 571 (Div. 2) {1186} | PROGRAMMING | E | 1600 | |
| 17566 | Odd Sum Segments | constructive algorithms math | Statement | B | Codeforces Round 575 (Div. 3) {1196} | PROGRAMMING | Editorial | 1200 | |
| 29170 | Three Piles of Candies | brute force constructive algorithms math | Statement | A | Codeforces Round 575 (Div. 3) {1196} | PROGRAMMING | Editorial | 700 | |
| 5475 | Print a 1337-string... | combinatorics constructive algorithms math strings | Statement | D | Educational Codeforces Round 70 (Rated for Div. 2) {1202} | PROGRAMMING | 68972 | 1900 | |
| 14726 | Almost Equal | constructive algorithms greedy math | Statement | A | Codeforces Round 580 (Div. 1) {1205} | PROGRAMMING | 69158 | 1300 | |
| 140 | Beauty of a Permutation | constructive algorithms math | Statement | F | Codeforces Round 580 (Div. 1) {1205} | PROGRAMMING | 69158 | 3400 | |
| 2866 | Petya and Construction Set | constructive algorithms graphs math sortings trees | Statement | E | Codeforces Round 583 (Div. 1 + Div. 2, based on Olympiad of Metropolises) {1214} | PROGRAMMING | Tutorial | 2000 | |
| 13280 | Tile Painting | constructive algorithms math number theory | Statement | A | Codeforces Round 599 (Div. 1) {1242} | PROGRAMMING | Codeforces Round #599 Editorial | 1500 | |
| 1547 | Running in Pairs | constructive algorithms greedy math | Statement | G | Codeforces Round 592 (Div. 2) {1244} | PROGRAMMING | Codeforces Round #592 (Div. 2) Tutorial | 2500 | |
| 2800 | The Feast and the Bus | brute force constructive algorithms greedy math | Statement | B | 2019-2020 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules, Teams Preferred) {1250} | PROGRAMMING | 1900 | ||
| 5033 | 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 | |
| 3430 | 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 | |
| 1601 | Point Ordering | constructive algorithms geometry interactive math | Statement | C | Codeforces Round 601 (Div. 1) {1254} | PROGRAMMING | Codeforces Round #601 Editorial | 2300 | |
| 16618 | Dice Tower | constructive algorithms math | Statement | B | Codeforces Global Round 6 {1266} | PROGRAMMING | Codeforces Global Round 6 Editorial | 1000 | |
| 10076 | Diverse Matrix | constructive algorithms greedy math number theory | Statement | C | Codeforces Global Round 6 {1266} | PROGRAMMING | Codeforces Global Round 6 Editorial | 1400 | |
| 3878 | Decreasing Debts | constructive algorithms data structures graphs greedy implementation math two pointers | Statement | D | Codeforces Global Round 6 {1266} | PROGRAMMING | Codeforces Global Round 6 Editorial | 2000 | |
| 17396 | Interesting Subarray | constructive algorithms greedy math | Statement | B | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 1300 | |
| 15058 | Make Good | bitmasks constructive algorithms math | Statement | C | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 1500 | |
| 4877 | Strange Device | constructive algorithms interactive math sortings | Statement | D | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 1900 | |
| 2751 | Divide Points | constructive algorithms geometry math | Statement | E | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 2300 | |
| 2977 | Subset with Zero Sum | constructive algorithms dfs and similar graphs math | Statement | G | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 2700 | |
| 318 | Xor on Figures | constructive algorithms fft math | Statement | I | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 3400 | |
| 1791 | Beautiful Rectangle | brute force combinatorics constructive algorithms data structures greedy math | Statement | C | Codeforces Round 606 (Div. 1, based on Technocup 2020 Elimination Round 4) {1276} | PROGRAMMING | Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial | 2300 | |
| 109 | Intergalactic Sliding Puzzle | combinatorics constructive algorithms math | Statement | F | Codeforces Round 607 (Div. 1) {1280} | PROGRAMMING | Codeforces Round #607 Editorial | 3400 | |
| 14179 | Friends and Gifts | constructive algorithms data structures math | Statement | C | Codeforces Round 611 (Div. 3) {1283} | PROGRAMMING | Codeforces Round #611 (Div. 3) Editorial | 1500 | |
| 1581 | Madhouse (Easy version) | brute force constructive algorithms interactive math | Statement | C1 | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 2400 | |
| 746 | Madhouse (Hard version) | brute force constructive algorithms hashing interactive math | Statement | C2 | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 2900 | |
| 298 | Harry The Potter | brute force constructive algorithms dp fft implementation math | Statement | F | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 3200 | |
| 466 | Rin and The Unknown Flower | constructive algorithms greedy interactive math | Statement | E | Codeforces Round 614 (Div. 1) {1292} | PROGRAMMING | 2250.0 | Codeforces Round #614 Editorial | 3500 |
| 3274 | Kuroni and the Score Distribution | constructive algorithms greedy implementation math | Statement | E | Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} | PROGRAMMING | 2000.0 | Ozon Tech Challenge 2020 Editorial | 2100 |
| 7014 | Different Rules | binary search constructive algorithms greedy implementation math | Statement | B | Codeforces Round 622 (Div. 2) {1313} | PROGRAMMING | 1000.0 | Editorial | 1700 |
| 7602 | Primitive Primes | constructive algorithms math ternary search | Statement | C | CodeCraft-20 (Div. 2) {1316} | PROGRAMMING | 1500.0 | Codecraft-20 (Div.2) Editorial | 1700 |
| 4661 | Present | binary search bitmasks constructive algorithms data structures math sortings | Statement | B | Codeforces Round 626 (Div. 1, based on Moscow Open Olympiad in Informatics) {1322} | PROGRAMMING | 1000.0 | Codeforces Round #626 Editorial | |
| 9715 | Dreamoon Likes Coloring | constructive algorithms greedy implementation math | Statement | A | Codeforces Round 631 (Div. 1) - Thanks, Denis aramis Shitov! {1329} | PROGRAMMING | 500.0 | Codeforces Round #631 Editorial | 1800 |
| 19191 | Composite Coloring | brute force constructive algorithms greedy math number theory | Statement | B | Codeforces Round 630 (Div. 2) {1332} | PROGRAMMING | 1000.0 | Codeforces Round #630 Editorial | 1500 |
| 8451 | Walk on Matrix | bitmasks constructive algorithms math | Statement | D | Codeforces Round 630 (Div. 2) {1332} | PROGRAMMING | 1250.0 | Codeforces Round #630 Editorial | 1700 |
| 4325 | Height All the Same | combinatorics constructive algorithms math matrices | Statement | E | Codeforces Round 630 (Div. 2) {1332} | PROGRAMMING | 1750.0 | Codeforces Round #630 Editorial | 2100 |
| 4138 | Challenges in school №41 | brute force constructive algorithms games graphs greedy implementation sortings | Statement | D | Codeforces Round 632 (Div. 2) {1333} | PROGRAMMING | 1750.0 | Codeforces Round #632 (Div. 2) editorial | |
| 18005 | Circle of Monsters | brute force constructive algorithms greedy math | Statement | C | Educational Codeforces Round 85 (Rated for Div. 2) {1334} | PROGRAMMING | Educational Codeforces Round 85 Editorial | ||
| 43093 | Ichihime and Triangle | constructive algorithms math | Statement | A | Codeforces Round 635 (Div. 2) {1337} | PROGRAMMING | 500.0 | Codeforces Round #635 Editorial | 1000 |
| 3450 | Perfect Triples | bitmasks brute force constructive algorithms divide and conquer greedy implementation math | Statement | C | Codeforces Round 633 (Div. 1) {1338} | PROGRAMMING | 1500.0 | Editorial | |
| 9575 | Edge Weight Assignment | bitmasks constructive algorithms greedy math trees | Statement | B | Codeforces Round 633 (Div. 1) {1338} | PROGRAMMING | 1000.0 | Editorial | |
| 65572 | Balanced Array | constructive algorithms math | Statement | B | Codeforces Round 636 (Div. 3) {1343} | PROGRAMMING | 76352 | 800 | |
| 9359 | Phoenix and Science | binary search bitmasks constructive algorithms greedy math | Statement | D | Codeforces Round 638 (Div. 2) {1348} | PROGRAMMING | 2000.0 | Codeforces Round #638 (Div. 2) Editorial | 1900 |
| 8976 | Orac and Medians | constructive algorithms greedy math | Statement | B | Codeforces Round 641 (Div. 1) {1349} | PROGRAMMING | 1250.0 | Codeforces Round #641 Editorial | 2000 |
| 45120 | Same Parity Summands | constructive algorithms math | Statement | B | Codeforces Round 640 (Div. 4) {1352} | PROGRAMMING | 77161 | 1200 | |
| 19589 | Binary String Reconstruction | constructive algorithms dfs and similar math | Statement | F | Codeforces Round 640 (Div. 4) {1352} | PROGRAMMING | 77161 | 1500 | |
| 44719 | Most Unstable Array | constructive algorithms greedy math | Statement | A | Codeforces Round 642 (Div. 3) {1353} | PROGRAMMING | Codeforces Round #642 (Div. 3) Editorial | 800 | |
| 19090 | Game With Array | constructive algorithms math | Statement | D | Codeforces Round 643 (Div. 2) {1355} | PROGRAMMING | 1500.0 | Codeforces Round #643 (Div. 2) Editorial | 1400 |
| 8370 | A/B Matrix | constructive algorithms flows greedy math number theory | Statement | G | Codeforces Round 644 (Div. 3) {1360} | PROGRAMMING | Codeforces Round #644 (Div. 3) Editorial | 1900 | |
| 1424 | Secure Password | bitmasks combinatorics constructive algorithms interactive math | Statement | G | Codeforces Round 648 (Div. 2) {1365} | PROGRAMMING | 3000.0 | Editorial — Codeforces Round #648 | 2800 |
| 12443 | Two Divisors | constructive algorithms math number theory | Statement | D | Educational Codeforces Round 89 (Rated for Div. 2) {1366} | PROGRAMMING | Educational Codeforces Round 89 Editorial | ||
| 25243 | Social Distance | constructive algorithms greedy math | Statement | C | Codeforces Round 650 (Div. 3) {1367} | PROGRAMMING | Codeforces Round #650 (Div. 3) Editorial | ||
| 21564 | Codeforces Subsequences | brute force constructive algorithms greedy math strings | Statement | B | Codeforces Global Round 8 {1368} | PROGRAMMING | 1000.0 | Codeforces Global Round 8: editorial | |
| 25141 | GCD Compression | brute force constructive algorithms math number theory | Statement | B | Codeforces Round 651 (Div. 2) {1370} | PROGRAMMING | 1000.0 | Editorial — Codeforces Round #651 | |
| 21408 | A Cookie for You | constructive algorithms greedy implementation math | Statement | C | Codeforces Round 654 (Div. 2) {1371} | PROGRAMMING | 1250.0 | Codeforces Round #654 (Div. 2) Editorial | |
| 13729 | Grid-00100 | constructive algorithms greedy math | Statement | D | Codeforces Round 654 (Div. 2) {1371} | PROGRAMMING | 1500.0 | Codeforces Round #654 (Div. 2) Editorial | |
| 19620 | Magical Calendar | constructive algorithms math | Statement | B | Codeforces Round 654 (Div. 2) {1371} | PROGRAMMING | 1000.0 | Codeforces Round #654 (Div. 2) Editorial | |
| 36820 | Omkar and Last Class of Math | constructive algorithms greedy math number theory | Statement | B | Codeforces Round 655 (Div. 2) {1372} | PROGRAMMING | 1000.0 | Codeforces Round #655 Editorial | 1300 |
| 19125 | Omkar and Baseball | constructive algorithms math | Statement | C | Codeforces Round 655 (Div. 2) {1372} | PROGRAMMING | 1500.0 | Codeforces Round #655 Editorial | 1500 |
| 5731 | Omkar and Circle | brute force constructive algorithms dp games greedy | Statement | D | Codeforces Round 655 (Div. 2) {1372} | PROGRAMMING | 2000.0 | Codeforces Round #655 Editorial | 2100 |
| 2963 | Sum of Digits | brute force constructive algorithms dp greedy math number theory | Statement | E | Educational Codeforces Round 90 (Rated for Div. 2) {1373} | PROGRAMMING | Educational Codeforces Round 90 Editorial | ||
| 2513 | Integer Game | brute force constructive algorithms games interactive math | Statement | F | Codeforces Global Round 9 {1375} | PROGRAMMING | 2000.0 | 79731 | |
| 474 | Inverse Genealogy | constructive algorithms divide and conquer dp math trees | Statement | E | Codeforces Round 657 (Div. 2) {1379} | PROGRAMMING | 2500.0 | Codeforces Round #657 Editorial | 2400 |
| 5462 | GameGame | bitmasks constructive algorithms dp games greedy math | Statement | B | Codeforces Round 659 (Div. 1) {1383} | PROGRAMMING | 1000.0 | Codeforces Round #659 Editorial | |
| 350 | Colors | *special binary search constructive algorithms interactive | Statement | A | Baltic Olympiad in Informatics 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1386} | PROGRAMMING | T | ||
| 50336 | LCM Problem | constructive algorithms greedy math number theory | Statement | A | Educational Codeforces Round 92 (Rated for Div. 2) {1389} | PROGRAMMING | 80809 | ||
| 25081 | Suborrays | constructive algorithms math | Statement | A | Codeforces Round 663 (Div. 2) {1391} | PROGRAMMING | 500.0 | Codeforces Round #663 (Div. 2) Editorial | |
| 2409 | Omkar and Landslide | binary search constructive algorithms greedy math | Statement | F | Codeforces Global Round 10 {1392} | PROGRAMMING | 2500.0 | Codeforces Global Round 10 — Editorial | |
| 3757 | Omkar and Duck | bitmasks constructive algorithms interactive math | Statement | E | Codeforces Global Round 10 {1392} | PROGRAMMING | 2000.0 | Codeforces Global Round 10 — Editorial | |
| 9892 | Omkar and Bed Wars | constructive algorithms dp greedy math strings | Statement | D | Codeforces Global Round 10 {1392} | PROGRAMMING | 1500.0 | Codeforces Global Round 10 — Editorial | |
| 11062 | Pinkie Pie Eats Patty-cakes | binary search constructive algorithms data structures greedy math sortings | Statement | C | Codeforces Round 662 (Div. 2) {1393} | PROGRAMMING | 1500.0 | Codeforces Round #662 Editorial | |
| 10580 | Maximum Distributed Tree | constructive algorithms dfs and similar greedy math number theory sortings trees | Statement | D | Codeforces Round 665 (Div. 2) {1401} | PROGRAMMING | 1750.0 | Codeforces Round #665 (Div. 2) Editorial | |
| 21798 | Ternary Sequence | constructive algorithms greedy math | Statement | B | Codeforces Round 665 (Div. 2) {1401} | PROGRAMMING | 1000.0 | Codeforces Round #665 (Div. 2) Editorial | |
| 26952 | Mere Array | constructive algorithms math number theory number theory sortings sortings | Statement | C | Codeforces Round 665 (Div. 2) {1401} | PROGRAMMING | 1500.0 | Codeforces Round #665 (Div. 2) Editorial | |
| 1278 | Game of Pairs | constructive algorithms dfs and similar interactive math number theory | Statement | D | Codeforces Round 668 (Div. 1) {1404} | PROGRAMMING | 2250.0 | Codeforces Round #668 Editorial | |
| 14952 | Chocolate Bunny | constructive algorithms interactive math two pointers | Statement | C | Codeforces Round 669 (Div. 2) {1407} | PROGRAMMING | 1500.0 | Codeforces Round #669 Editorial |