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16443 Diverse Garland constructive algorithms dp greedy Statement D Codeforces Round 535 (Div. 3) {1108} PROGRAMMING 64751 1400
4536 Sasha and One More Name constructive algorithms hashing strings Statement B Codeforces Round 539 (Div. 1) {1109} PROGRAMMING Codeforces Round #539 Editorial 1800
9995 Meaningless Operations constructive algorithms math number theory Statement C Codeforces Global Round 1 {1110} PROGRAMMING The Editorial of the First Codeforces Global Round 1500
4699 Magic Stones constructive algorithms math sortings Statement E Codeforces Global Round 1 {1110} PROGRAMMING The Editorial of the First Codeforces Global Round 2200
740 Tree-Tac-Toe constructive algorithms games trees Statement G Codeforces Global Round 1 {1110} PROGRAMMING The Editorial of the First Codeforces Global Round 3000
9389 Yet Another Array Partitioning Task constructive algorithms greedy sortings Statement B Codeforces Round 538 (Div. 2) {1114} PROGRAMMING Codeforces Round #538 (Div. 2) Editorial 1500
1635 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
6093 Palindromic Matrix constructive algorithms implementation Statement C Codeforces Round 540 (Div. 3) {1118} PROGRAMMING 65396 1700
4447 Yet Another Ball Problem constructive algorithms implementation Statement E Codeforces Round 540 (Div. 3) {1118} PROGRAMMING 65396 2000
7174 Ramesses and Corner Inversion constructive algorithms greedy implementation math Statement C Codeforces Global Round 2 {1119} PROGRAMMING Codeforces Global Round 2 Editorial 1500
568 Get Ready for the Battle constructive algorithms implementation Statement G Codeforces Global Round 2 {1119} PROGRAMMING Codeforces Global Round 2 Editorial 3000
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
7729 Asya And Kittens constructive algorithms dsu Statement F Codeforces Round 541 (Div. 2) {1131} PROGRAMMING Codeforces Round #541 Editorial 1700
3797 Spanning Tree with One Fixed Degree constructive algorithms dfs and similar dsu graphs greedy Statement F2 Codeforces Round 544 (Div. 3) {1133} PROGRAMMING Codeforces Round #544 (Div. 3) Editorial 2200
12267 Nastya Is Playing Computer Games constructive algorithms math Statement B Codeforces Round 546 (Div. 2) {1136} PROGRAMMING Editorial of Round #546(Div.2) 1000
8023 Nastya Is Transposing Matrices constructive algorithms sortings Statement C Codeforces Round 546 (Div. 2) {1136} PROGRAMMING Editorial of Round #546(Div.2) 1500
2141 Cooperative Game constructive algorithms interactive number theory Statement D Codeforces Round 545 (Div. 1) {1137} PROGRAMMING Codeforces Round #545 – Editorial 2500
2542 Privatization of Roads in Treeland binary search constructive algorithms dfs and similar graphs greedy trees Statement G Codeforces Round 547 (Div. 3) {1141} PROGRAMMING 66062 2500
16319 Two Shuffled Sequences constructive algorithms sortings Statement C Codeforces Round 550 (Div. 3) {1144} PROGRAMMING 66307 1100
10825 Equalize Them All constructive algorithms greedy Statement D Codeforces Round 550 (Div. 3) {1144} PROGRAMMING 66307 1400
5613 Crazy Diamond constructive algorithms sortings Statement C Codeforces Global Round 3 {1148} PROGRAMMING Codeforces Global Round 3 Editorial 1700
1819 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
387 Gold Experience constructive algorithms graphs math number theory probabilities Statement G Codeforces Global Round 3 {1148} PROGRAMMING Codeforces Global Round 3 Editorial 3100
17778 Prefix Sum Primes constructive algorithms greedy math number theory Statement A Codeforces Round 556 (Div. 1) {1149} PROGRAMMING 66783 1300
12803 Dima and a Bad XOR bitmasks brute force constructive algorithms dp Statement B Codeforces Round 553 (Div. 2) {1151} PROGRAMMING Codeforces Round #553 (Div. 2) Editorial 1600
5597 Problem for Nazar constructive algorithms math Statement C Codeforces Round 553 (Div. 2) {1151} PROGRAMMING Codeforces Round #553 (Div. 2) Editorial 1700
9302 Neko Performs Cat Furrier Transform bitmasks constructive algorithms dfs and similar math Statement B Codeforces Round 554 (Div. 2) {1152} PROGRAMMING T 1300
1123 Neko and Flashback constructive algorithms dfs and similar graphs Statement E Codeforces Round 554 (Div. 2) {1152} PROGRAMMING T 2500
9399 Serval and Toy Bricks constructive algorithms greedy Statement B Codeforces Round 551 (Div. 2) {1153} PROGRAMMING Editorial 1200
3991 N Problems During K Days constructive algorithms greedy math Statement D Codeforces Round 555 (Div. 3) {1157} PROGRAMMING 66737 2100
2877 Maximum Balanced Circle constructive algorithms dp greedy two pointers Statement F Codeforces Round 555 (Div. 3) {1157} PROGRAMMING 66737 2300
8308 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
2380 The minimal unique substring constructive algorithms math strings Statement B Codeforces Round 559 (Div. 1) {1158} PROGRAMMING 66993 2200
2114 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
1008 Magical Permutation bitmasks brute force constructive algorithms data structures graphs math Statement E Codeforces Round 558 (Div. 2) {1163} PROGRAMMING 66943 2800
11913 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
3006 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
7366 Bicolored RBS constructive algorithms greedy Statement D Educational Codeforces Round 65 (Rated for Div. 2) {1167} PROGRAMMING 67058 1500
428 Xor Permutations constructive algorithms math Statement E Codeforces Round 562 (Div. 1) {1168} PROGRAMMING Codeforces Round #562 — Editorial 3100
9438 Nauuo and Chess constructive algorithms greedy Statement B Codeforces Round 564 (Div. 2) {1173} PROGRAMMING Codeforces Round #564 Editorial 1100
19186 Ehab Fails to Be Thanos constructive algorithms greedy sortings Statement A Codeforces Round 563 (Div. 2) {1174} PROGRAMMING Codeforces round #563 editorial 1000
12764 Ehab and a Special Coloring Problem constructive algorithms number theory Statement C Codeforces Round 563 (Div. 2) {1174} PROGRAMMING Codeforces round #563 editorial 1300
1956 Ehab and the Big Finale constructive algorithms divide and conquer graphs implementation interactive trees Statement F Codeforces Round 563 (Div. 2) {1174} PROGRAMMING Codeforces round #563 editorial 2300
7903 Prime Graph constructive algorithms greedy math number theory Statement D Codeforces Global Round 4 {1178} PROGRAMMING E 1600
4502 Archaeology brute force constructive algorithms greedy strings Statement E Codeforces Global Round 4 {1178} PROGRAMMING E 1900
1001 Complete Mirror constructive algorithms dfs and similar dp hashing implementation trees Statement D Codeforces Round 566 (Div. 2) {1182} PROGRAMMING 67614 2500
9303 Vus the Cossack and Numbers constructive algorithms greedy math Statement D Codeforces Round 571 (Div. 2) {1186} PROGRAMMING E 1600
6753 Vasya And Array constructive algorithms greedy implementation Statement C Educational Codeforces Round 67 (Rated for Div. 2) {1187} PROGRAMMING Разбор Educational Codeforces Round 67 1800
1296 Add on a Tree: Revolution constructive algorithms dfs and similar implementation trees Statement A2 Codeforces Round 572 (Div. 1) {1188} PROGRAMMING Editorial of Codeforces Round #572 2500
48 Scissors and Tape *special constructive algorithms geometry Statement C CEOI 2019 day 2 online mirror (unrated, IOI format) {1193} PROGRAMMING T
17529 Odd Sum Segments constructive algorithms math Statement B Codeforces Round 575 (Div. 3) {1196} PROGRAMMING Editorial 1200
3912 Connected Component on a Chessboard constructive algorithms implementation Statement E Codeforces Round 575 (Div. 3) {1196} PROGRAMMING Editorial 1900
3143 K-th Path brute force constructive algorithms shortest paths sortings Statement F Codeforces Round 575 (Div. 3) {1196} PROGRAMMING Editorial 2500
29109 Three Piles of Candies brute force constructive algorithms math Statement A Codeforces Round 575 (Div. 3) {1196} PROGRAMMING Editorial 700
4045 Matching vs Independent Set constructive algorithms graphs greedy sortings Statement C Codeforces Round 576 (Div. 1) {1198} PROGRAMMING E 2200
5455 Print a 1337-string... combinatorics constructive algorithms math strings Statement D Educational Codeforces Round 70 (Rated for Div. 2) {1202} PROGRAMMING 68972 1900
14695 Almost Equal constructive algorithms greedy math Statement A Codeforces Round 580 (Div. 1) {1205} PROGRAMMING 69158 1300
762 Almost All constructive algorithms trees Statement D Codeforces Round 580 (Div. 1) {1205} PROGRAMMING 69158 2800
139 Beauty of a Permutation constructive algorithms math Statement F Codeforces Round 580 (Div. 1) {1205} PROGRAMMING 69158 3400
13749 Square Filling constructive algorithms greedy implementation Statement B Educational Codeforces Round 71 (Rated for Div. 2) {1207} PROGRAMMING Educational Codeforces Round 71 Editorial 1200
7852 Paint the Digits constructive algorithms greedy implementation Statement C Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} PROGRAMMING 69791 1600
2859 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
458 Tiles Placement constructive algorithms dfs and similar trees Statement H Codeforces Round 583 (Div. 1 + Div. 2, based on Olympiad of Metropolises) {1214} PROGRAMMING Tutorial 2700
11923 Swap Letters constructive algorithms greedy Statement C Codeforces Round 585 (Div. 2) {1215} PROGRAMMING Codeforces Round #585 Editorial 1500
5934 Coloring Edges constructive algorithms dfs and similar graphs Statement D Educational Codeforces Round 72 (Rated for Div. 2) {1217} PROGRAMMING Educational Codeforces Round 72 Editorial 2000
162 Alpha planetary system constructive algorithms graphs shortest paths Statement G Bubble Cup 12 - Finals [Online Mirror, unrated, Div. 1] {1218} PROGRAMMING E 3300
12514 Knights constructive algorithms greedy Statement B Educational Codeforces Round 73 (Rated for Div. 2) {1221} PROGRAMMING Разбор Educational Codeforces Round 73 1100
990 Tree Factory constructive algorithms greedy trees Statement F Technocup 2020 - Elimination Round 2 {1225} PROGRAMMING 70898 2500
658 To Make 1 bitmasks constructive algorithms dp greedy number theory Statement G Technocup 2020 - Elimination Round 2 {1225} PROGRAMMING 70898 3000
5412 Complete Tripartite brute force constructive algorithms graphs hashing implementation Statement D Codeforces Round 589 (Div. 2) {1228} PROGRAMMING 70162 1800
479 One Node is Gone constructive algorithms implementation trees Statement F Codeforces Round 589 (Div. 2) {1228} PROGRAMMING 70162 2700
932 Middle-Out constructive algorithms greedy strings Statement E Dasha Code Championship - Novosibirsk Finals Round (only for onsite-finalists) {1231} PROGRAMMING Dasha Code Championship Finals and Mirror Round 588 Editorial 2000
10542 Labs constructive algorithms greedy implementation Statement C Codeforces Round 593 (Div. 2) {1236} PROGRAMMING 70654 1300
6297 Balanced Removals (Easier) constructive algorithms geometry greedy Statement C1 Codeforces Global Round 5 {1237} PROGRAMMING T 1600
4532 Balanced Removals (Harder) binary search constructive algorithms divide and conquer greedy implementation sortings Statement C2 Codeforces Global Round 5 {1237} PROGRAMMING T 1900
13255 Tile Painting constructive algorithms math number theory Statement A Codeforces Round 599 (Div. 1) {1242} PROGRAMMING Codeforces Round #599 Editorial 1500
155 Planar Perimeter constructive algorithms graphs Statement E Codeforces Round 599 (Div. 1) {1242} PROGRAMMING Codeforces Round #599 Editorial 3200
8293 Paint the Tree brute force constructive algorithms dp graphs implementation trees Statement D Codeforces Round 592 (Div. 2) {1244} PROGRAMMING Codeforces Round #592 (Div. 2) Tutorial 1700
6385 Minimizing Difference binary search constructive algorithms greedy sortings ternary search two pointers Statement E Codeforces Round 592 (Div. 2) {1244} PROGRAMMING Codeforces Round #592 (Div. 2) Tutorial 2000
1633 Chips constructive algorithms implementation Statement F Codeforces Round 592 (Div. 2) {1244} PROGRAMMING Codeforces Round #592 (Div. 2) Tutorial 2300
1519 Running in Pairs constructive algorithms greedy math Statement G Codeforces Round 592 (Div. 2) {1244} PROGRAMMING Codeforces Round #592 (Div. 2) Tutorial 2500
14515 Restricted RPS constructive algorithms dp greedy Statement B Codeforces Round 597 (Div. 2) {1245} PROGRAMMING Codeforces Round #597 (Div. 2) Editorial 1200
2798 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
391 SmartGarden constructive algorithms divide and conquer Statement M 2019-2020 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules, Teams Preferred) {1250} PROGRAMMING 2700
10229 Harmonious Graph constructive algorithms dfs and similar dsu graphs greedy sortings Statement D Codeforces Round 600 (Div. 2) {1253} PROGRAMMING Editorial 1700
5512 Feeding Chicken constructive algorithms greedy implementation Statement A Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 1900
5004 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
3416 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
1591 Point Ordering constructive algorithms geometry interactive math Statement C Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 2300
7213 League of Leesins constructive algorithms implementation Statement C Codeforces Round 601 (Div. 2) {1255} PROGRAMMING Codeforces Round #601 Editorial 1600
3620 Equalizing Two Strings constructive algorithms sortings strings Statement F Codeforces Round 598 (Div. 3) {1256} PROGRAMMING Codeforces Round #598 (Div. 3) Editorial 2200
6044 Beautiful Sequence brute force constructive algorithms greedy Statement B Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 1900
925 Beautiful League constructive algorithms flows graph matchings Statement E Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 2700
1093 Beautiful Fibonacci Problem constructive algorithms number theory Statement F Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 3600
15923 Beautiful String constructive algorithms greedy Statement A Codeforces Round 604 (Div. 2) {1265} PROGRAMMING Codeforces Round #604 Editorial 1000
16562 Dice Tower constructive algorithms math Statement B Codeforces Global Round 6 {1266} PROGRAMMING Codeforces Global Round 6 Editorial 1000
10053 Diverse Matrix constructive algorithms greedy math number theory Statement C Codeforces Global Round 6 {1266} PROGRAMMING Codeforces Global Round 6 Editorial 1400
3868 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
3351 Lexicography constructive algorithms strings Statement L 2019-2020 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1267} PROGRAMMING nerc-2019-tutorial.pdf 1800
1068 Intriguing Selection brute force constructive algorithms implementation interactive sortings Statement I 2019-2020 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1267} PROGRAMMING nerc-2019-tutorial.pdf 2700
9060 Long Beautiful Integer constructive algorithms greedy implementation strings Statement A Codeforces Round 609 (Div. 1) {1268} PROGRAMMING Codeforces Round #609 — Editorial 1700
17341 Interesting Subarray constructive algorithms greedy math Statement B Good Bye 2019 {1270} PROGRAMMING Разбор Goodbye 2019 1300
15022 Make Good bitmasks constructive algorithms math Statement C Good Bye 2019 {1270} PROGRAMMING Разбор Goodbye 2019 1500
4862 Strange Device constructive algorithms interactive math sortings Statement D Good Bye 2019 {1270} PROGRAMMING Разбор Goodbye 2019 1900
2725 Divide Points constructive algorithms geometry math Statement E Good Bye 2019 {1270} PROGRAMMING Разбор Goodbye 2019 2300
2949 Subset with Zero Sum constructive algorithms dfs and similar graphs math Statement G Good Bye 2019 {1270} PROGRAMMING Разбор Goodbye 2019 2700
316 Xor on Figures constructive algorithms fft math Statement I Good Bye 2019 {1270} PROGRAMMING Разбор Goodbye 2019 3400
14667 Snow Walking Robot constructive algorithms greedy implementation Statement B Codeforces Round 605 (Div. 3) {1272} PROGRAMMING Codeforces Round #605 (Div. 3) Editorial 1200
1776 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
2041 Tests for problem D constructive algorithms dfs and similar divide and conquer trees Statement E Educational Codeforces Round 78 (Rated for Div. 2) {1278} PROGRAMMING Educational Codeforces Round 78 Editorial 2200
93 Intergalactic Sliding Puzzle combinatorics constructive algorithms math Statement F Codeforces Round 607 (Div. 1) {1280} PROGRAMMING Codeforces Round #607 Editorial 3400
2371 Enchanted Artifact constructive algorithms interactive strings Statement D Codeforces Round 610 (Div. 2) {1282} PROGRAMMING 72461 2300
1220 The Cake Is a Lie constructive algorithms data structures dfs and similar graphs Statement E Codeforces Round 610 (Div. 2) {1282} PROGRAMMING 72461 2400
14137 Friends and Gifts constructive algorithms data structures math Statement C Codeforces Round 611 (Div. 3) {1283} PROGRAMMING Codeforces Round #611 (Div. 3) Editorial 1500
2034 DIY Garland constructive algorithms greedy trees Statement F Codeforces Round 611 (Div. 3) {1283} PROGRAMMING Codeforces Round #611 (Div. 3) Editorial 2400
2000 Delete a Segment brute force constructive algorithms data structures dp graphs sortings trees two pointers Statement E Codeforces Round 613 (Div. 2) {1285} PROGRAMMING Codeforces Round #613 (Div. 2) Editorial 2300
5454 Numbers on Tree constructive algorithms data structures dfs and similar graphs greedy trees Statement B Codeforces Round 612 (Div. 1) {1286} PROGRAMMING Codeforces Round #612 - Editorial 2000
1577 Madhouse (Easy version) brute force constructive algorithms interactive math Statement C1 Codeforces Round 612 (Div. 1) {1286} PROGRAMMING Codeforces Round #612 - Editorial 2400
744 Madhouse (Hard version) brute force constructive algorithms hashing interactive math Statement C2 Codeforces Round 612 (Div. 1) {1286} PROGRAMMING Codeforces Round #612 - Editorial 2900
294 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
644 Red-Blue Graph constructive algorithms flows Statement F Educational Codeforces Round 80 (Rated for Div. 2) {1288} PROGRAMMING Educational Codeforces Round 80 Editorial 2900
7075 Irreducible Anagrams binary search constructive algorithms data structures strings two pointers Statement B Codeforces Round 616 (Div. 1) {1290} PROGRAMMING 1000.0 Codeforces Round #616 Editorial 1900
947 Coffee Varieties (hard version) constructive algorithms graphs interactive Statement D Codeforces Round 616 (Div. 1) {1290} PROGRAMMING 2500.0 Codeforces Round #616 Editorial 2900
6759 Aroma's Search brute force constructive algorithms geometry greedy implementation Statement B Codeforces Round 614 (Div. 1) {1292} PROGRAMMING 750.0 Codeforces Round #614 Editorial 1800
462 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
8192 String Coloring (easy version) constructive algorithms dp graphs greedy sortings Statement E1 Codeforces Round 617 (Div. 3) {1296} PROGRAMMING Codeforces Round #617 (Div. 3) Editorial 1800
3086 Berland Beauty constructive algorithms dfs and similar greedy sortings trees Statement F Codeforces Round 617 (Div. 3) {1296} PROGRAMMING Codeforces Round #617 (Div. 3) Editorial 2400
4232 Time to Run constructive algorithms graphs implementation Statement D Codeforces Round 619 (Div. 2) {1301} PROGRAMMING 1750.0 Codeforces Round #619 (Div. 2) Editorial 1900
18743 Longest Palindrome brute force constructive algorithms greedy implementation strings Statement B Codeforces Round 620 (Div. 2) {1304} PROGRAMMING 1000.0 Codeforces Round #620 (Div. 2) Editorial 1100
6678 Shortest and Longest LIS constructive algorithms graphs greedy two pointers Statement D Codeforces Round 620 (Div. 2) {1304} PROGRAMMING 1750.0 Codeforces Round #620 (Div. 2) Editorial 1800
12348 Kuroni and Simple Strings constructive algorithms greedy strings two pointers Statement B Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} PROGRAMMING 1000.0 Ozon Tech Challenge 2020 Editorial 1300
5354 Kuroni and the Celebration constructive algorithms dfs and similar graphs interactive trees Statement D Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} PROGRAMMING 1750.0 Ozon Tech Challenge 2020 Editorial 1900
3265 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
14639 Kuroni and the Gifts brute force constructive algorithms greedy sortings Statement A Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} PROGRAMMING 500.0 Ozon Tech Challenge 2020 Editorial 800
2711 Construct the Binary Tree brute force constructive algorithms dfs and similar trees Statement E Codeforces Round 624 (Div. 3) {1311} PROGRAMMING 74224 2400
38725 Bogosort constructive algorithms sortings Statement B Educational Codeforces Round 83 (Rated for Div. 2) {1312} PROGRAMMING 74640
7006 Different Rules binary search constructive algorithms greedy implementation math Statement B Codeforces Round 622 (Div. 2) {1313} PROGRAMMING 1000.0 Editorial 1700
11719 String Modification brute force constructive algorithms implementation sortings strings Statement B CodeCraft-20 (Div. 2) {1316} PROGRAMMING 1000.0 Codecraft-20 (Div.2) Editorial 1400
7585 Primitive Primes constructive algorithms math ternary search Statement C CodeCraft-20 (Div. 2) {1316} PROGRAMMING 1500.0 Codecraft-20 (Div.2) Editorial 1700
3537 Nash Matrix constructive algorithms dfs and similar graphs implementation Statement D CodeCraft-20 (Div. 2) {1316} PROGRAMMING 1750.0 Codecraft-20 (Div.2) Editorial 2000
4622 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
17032 Ehab and Path-etic MEXs constructive algorithms dfs and similar greedy trees Statement C Codeforces Round 628 (Div. 2) {1325} PROGRAMMING 1250.0 74235 1500
13553 Ehab the Xorcist bitmasks constructive algorithms greedy number theory Statement D Codeforces Round 628 (Div. 2) {1325} PROGRAMMING 1750.0 74235 1700
2319 Ehab's Last Theorem constructive algorithms dfs and similar graphs greedy Statement F Codeforces Round 628 (Div. 2) {1325} PROGRAMMING 2750.0 74235 2600
46052 EhAb AnD gCd constructive algorithms greedy number theory Statement A Codeforces Round 628 (Div. 2) {1325} PROGRAMMING 500.0 74235 800
32635 Bad Ugly Numbers constructive algorithms number theory Statement A Codeforces Global Round 7 {1326} PROGRAMMING 500.0 74961 1000
9656 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
1802 Drazil Likes Heap constructive algorithms data structures greedy implementation sortings Statement C Codeforces Round 631 (Div. 1) - Thanks, Denis aramis Shitov! {1329} PROGRAMMING 1500.0 Codeforces Round #631 Editorial 2400
535 Dreamoon Likes Strings constructive algorithms data structures Statement D Codeforces Round 631 (Div. 1) - Thanks, Denis aramis Shitov! {1329} PROGRAMMING 2000.0 Codeforces Round #631 Editorial 3000
18917 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
8439 Walk on Matrix bitmasks constructive algorithms math Statement D Codeforces Round 630 (Div. 2) {1332} PROGRAMMING 1250.0 Codeforces Round #630 Editorial 1700
4300 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
4128 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
17883 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
7718 Minimum Euler Cycle constructive algorithms graphs greedy implementation Statement D Educational Codeforces Round 85 (Rated for Div. 2) {1334} PROGRAMMING Educational Codeforces Round 85 Editorial
29413 Anti-Sudoku constructive algorithms implementation Statement D Codeforces Round 634 (Div. 3) {1335} PROGRAMMING 75993 1300
524 Yui and Mahjong Set constructive algorithms interactive Statement D Codeforces Round 635 (Div. 1) {1336} PROGRAMMING 2250.0 Codeforces Round #635 Editorial 3000
42814 Ichihime and Triangle constructive algorithms math Statement A Codeforces Round 635 (Div. 2) {1337} PROGRAMMING 500.0 Codeforces Round #635 Editorial 1000
3436 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
9502 Edge Weight Assignment bitmasks constructive algorithms greedy math trees Statement B Codeforces Round 633 (Div. 1) {1338} PROGRAMMING 1000.0 Editorial
28289 Sorted Adjacent Differences constructive algorithms sortings Statement B Codeforces Round 633 (Div. 2) {1339} PROGRAMMING 750.0 Codeforces Round #633 Editorial
1068 Nastya and Time Machine constructive algorithms dfs and similar graphs trees Statement D Codeforces Round 637 (Div. 1) - Thanks, Ivan Belonogov! {1340} PROGRAMMING 1750.0 Codeforces Round #637 Editorial
24569 Binary Period constructive algorithms strings Statement B Educational Codeforces Round 86 (Rated for Div. 2) {1342} PROGRAMMING 76633 1200
6362 Multiple Testcases binary search constructive algorithms data structures greedy sortings two pointers Statement D Educational Codeforces Round 86 (Rated for Div. 2) {1342} PROGRAMMING 76633 1900
1392 Restore the Permutation by Sorted Segments brute force constructive algorithms data structures greedy implementation Statement F Codeforces Round 636 (Div. 3) {1343} PROGRAMMING 76352 2800
64862 Balanced Array constructive algorithms math Statement B Codeforces Round 636 (Div. 3) {1343} PROGRAMMING 76352 800
6348 Monopole Magnets constructive algorithms dfs and similar dsu graphs Statement B Codeforces Round 639 (Div. 1) {1344} PROGRAMMING 1000.0 Codeforces Round #639 Editorial 2000
27432 Phoenix and Beauty constructive algorithms data structures greedy Statement B Codeforces Round 638 (Div. 2) {1348} PROGRAMMING 1000.0 Codeforces Round #638 (Div. 2) Editorial 1400
15469 Phoenix and Distribution constructive algorithms greedy strings Statement C Codeforces Round 638 (Div. 2) {1348} PROGRAMMING 1500.0 Codeforces Round #638 (Div. 2) Editorial 1600
9335 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
8929 Orac and Medians constructive algorithms greedy math Statement B Codeforces Round 641 (Div. 1) {1349} PROGRAMMING 1250.0 Codeforces Round #641 Editorial 2000
120 Slime and Hats constructive algorithms dp greedy Statement E Codeforces Round 641 (Div. 1) {1349} PROGRAMMING 2500.0 Codeforces Round #641 Editorial 3500
44652 Same Parity Summands constructive algorithms math Statement B Codeforces Round 640 (Div. 4) {1352} PROGRAMMING 77161 1200
19353 Binary String Reconstruction constructive algorithms dfs and similar math Statement F Codeforces Round 640 (Div. 4) {1352} PROGRAMMING 77161 1500
20228 Constructing the Array constructive algorithms data structures sortings Statement D Codeforces Round 642 (Div. 3) {1353} PROGRAMMING Codeforces Round #642 (Div. 3) Editorial 1600
44511 Most Unstable Array constructive algorithms greedy math Statement A Codeforces Round 642 (Div. 3) {1353} PROGRAMMING Codeforces Round #642 (Div. 3) Editorial 800
1474 Summoning Minions constructive algorithms dp flows graph matchings greedy sortings Statement F Educational Codeforces Round 87 (Rated for Div. 2) {1354} PROGRAMMING 77593 2500
19034 Game With Array constructive algorithms math Statement D Codeforces Round 643 (Div. 2) {1355} PROGRAMMING 1500.0 Codeforces Round #643 (Div. 2) Editorial 1400
959 Guess Divisors Count constructive algorithms interactive number theory Statement F Codeforces Round 643 (Div. 2) {1355} PROGRAMMING 3000.0 Codeforces Round #643 (Div. 2) Editorial 2600
2449 Are You Fired? constructive algorithms data structures dp greedy implementation Statement E Codeforces Round 645 (Div. 2) {1358} PROGRAMMING 2000.0 Codeforces Round #645 (Div. 2) Editorial 2400
501 Tasty Cookie binary search constructive algorithms greedy implementation Statement F Codeforces Round 645 (Div. 2) {1358} PROGRAMMING 2500.0 Codeforces Round #645 (Div. 2) Editorial 2700
36653 Similar Pairs constructive algorithms graph matchings greedy sortings Statement C Codeforces Round 644 (Div. 3) {1360} PROGRAMMING Codeforces Round #644 (Div. 3) Editorial 1100
13499 Spy-string bitmasks brute force constructive algorithms dp hashing strings Statement F Codeforces Round 644 (Div. 3) {1360} PROGRAMMING Codeforces Round #644 (Div. 3) Editorial 1700
8332 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
8757 Johnny and Contribution constructive algorithms graphs greedy sortings Statement A Codeforces Round 647 (Div. 1) - Thanks, Algo Muse! {1361} PROGRAMMING 500.0 Codeforces Round #647 Editorial 1700
1828 Johnny and Megan's Necklace binary search bitmasks constructive algorithms dfs and similar dsu graphs Statement C Codeforces Round 647 (Div. 1) - Thanks, Algo Muse! {1361} PROGRAMMING 2000.0 Codeforces Round #647 Editorial 2500
14323 Ehab and Prefix MEXs brute force constructive algorithms greedy Statement C Codeforces Round 649 (Div. 2) {1364} PROGRAMMING 1500.0 Codeforces round #649 editorial 1600
4951 Ehab's Last Corollary constructive algorithms data structures dfs and similar dp graphs implementation trees Statement D Codeforces Round 649 (Div. 2) {1364} PROGRAMMING 2000.0 Codeforces round #649 editorial 2100
1546 X-OR bitmasks constructive algorithms interactive probabilities Statement E Codeforces Round 649 (Div. 2) {1364} PROGRAMMING 2500.0 Codeforces round #649 editorial 2700
28799 Trouble Sort constructive algorithms implementation Statement B Codeforces Round 648 (Div. 2) {1365} PROGRAMMING 750.0 Editorial — Codeforces Round #648 1300
24942 Rotation Matching constructive algorithms data structures greedy implementation Statement C Codeforces Round 648 (Div. 2) {1365} PROGRAMMING 1250.0 Editorial — Codeforces Round #648 1400
20687 Solve The Maze constructive algorithms dfs and similar dsu graphs greedy implementation shortest paths Statement D Codeforces Round 648 (Div. 2) {1365} PROGRAMMING 1500.0 Editorial — Codeforces Round #648 1700
4740 Swaps Again constructive algorithms implementation sortings Statement F Codeforces Round 648 (Div. 2) {1365} PROGRAMMING 2500.0 Editorial — Codeforces Round #648 2100
1413 Secure Password bitmasks combinatorics constructive algorithms interactive math Statement G Codeforces Round 648 (Div. 2) {1365} PROGRAMMING 3000.0 Editorial — Codeforces Round #648 2800
12289 Two Divisors constructive algorithms math number theory Statement D Educational Codeforces Round 89 (Rated for Div. 2) {1366} PROGRAMMING Educational Codeforces Round 89 Editorial
8768 Task On The Board constructive algorithms greedy implementation sortings Statement D Codeforces Round 650 (Div. 3) {1367} PROGRAMMING Codeforces Round #650 (Div. 3) Editorial
25071 Social Distance constructive algorithms greedy math Statement C Codeforces Round 650 (Div. 3) {1367} PROGRAMMING Codeforces Round #650 (Div. 3) Editorial
21315 Codeforces Subsequences brute force constructive algorithms greedy math strings Statement B Codeforces Global Round 8 {1368} PROGRAMMING 1000.0 Codeforces Global Round 8: editorial
2359 Ski Accidents constructive algorithms dfs and similar greedy Statement E Codeforces Global Round 8 {1368} PROGRAMMING 2500.0 Codeforces Global Round 8: editorial
2450 DeadLee constructive algorithms data structures graphs greedy implementation sortings Statement E Codeforces Round 652 (Div. 2) {1369} PROGRAMMING 2500.0 Codeforces Round #652 (Div. 2) Editorial 2400
24972 GCD Compression brute force constructive algorithms math number theory Statement B Codeforces Round 651 (Div. 2) {1370} PROGRAMMING 1000.0 Editorial — Codeforces Round #651
21352 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
13668 Grid-00100 constructive algorithms greedy math Statement D Codeforces Round 654 (Div. 2) {1371} PROGRAMMING 1500.0 Codeforces Round #654 (Div. 2) Editorial
19595 Magical Calendar constructive algorithms math Statement B Codeforces Round 654 (Div. 2) {1371} PROGRAMMING 1000.0 Codeforces Round #654 (Div. 2) Editorial
36174 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
19072 Omkar and Baseball constructive algorithms math Statement C Codeforces Round 655 (Div. 2) {1372} PROGRAMMING 1500.0 Codeforces Round #655 Editorial 1500
5714 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
33453 Omkar and Completion constructive algorithms implementation Statement A Codeforces Round 655 (Div. 2) {1372} PROGRAMMING 500.0 Codeforces Round #655 Editorial 800
52280 01 Game brute force constructive algorithms dp games implementation strings Statement B Educational Codeforces Round 90 (Rated for Div. 2) {1373} PROGRAMMING Educational Codeforces Round 90 Editorial
2946 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
1392 Cyclic Shifts Sorting brute force constructive algorithms implementation Statement F Codeforces Round 653 (Div. 3) {1374} PROGRAMMING 79517
2502 Integer Game brute force constructive algorithms games interactive math Statement F Codeforces Global Round 9 {1375} PROGRAMMING 2000.0 79731
10050 Replace by MEX brute force constructive algorithms implementation Statement D Codeforces Global Round 9 {1375} PROGRAMMING 1750.0 79731
493 Set Merging constructive algorithms data structures divide and conquer Statement H Codeforces Global Round 9 {1375} PROGRAMMING 2750.0 79731
17840 Neighbor Grid constructive algorithms greedy Statement B Codeforces Global Round 9 {1375} PROGRAMMING 750.0 79731
22906 Element Extermination constructive algorithms greedy Statement C Codeforces Global Round 9 {1375} PROGRAMMING 1500.0 79731
3368 Inversion SwapSort constructive algorithms greedy sortings Statement E Codeforces Global Round 9 {1375} PROGRAMMING 2000.0 79731
472 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
21699 Prefix Flip (Easy Version) constructive algorithms data structures strings Statement A1 Codeforces Round 658 (Div. 1) {1381} PROGRAMMING 500.0 Codeforces Round #658 Editorial 1300
14276 Prefix Flip (Hard Version) constructive algorithms data structures strings two pointers Statement A2 Codeforces Round 658 (Div. 1) {1381} PROGRAMMING 500.0 Codeforces Round #658 Editorial 1700
1708 Mastermind constructive algorithms greedy implementation sortings Statement C Codeforces Round 658 (Div. 1) {1381} PROGRAMMING 2000.0 Codeforces Round #658 Editorial 2500
5431 GameGame bitmasks constructive algorithms dp games greedy math Statement B Codeforces Round 659 (Div. 1) {1383} PROGRAMMING 1000.0 Codeforces Round #659 Editorial
759 Rearrange brute force constructive algorithms graphs greedy sortings Statement D Codeforces Round 659 (Div. 1) {1383} PROGRAMMING 1750.0 Codeforces Round #659 Editorial
2588 Koa and the Beach (Hard Version) constructive algorithms greedy Statement B2 Codeforces Round 659 (Div. 2) {1384} PROGRAMMING 750.0 Codeforces Round #659 Editorial
19598 Common Prefixes constructive algorithms greedy strings Statement A Codeforces Round 659 (Div. 2) {1384} PROGRAMMING 500.0 Codeforces Round #659 Editorial
349 Colors *special binary search constructive algorithms interactive Statement A Baltic Olympiad in Informatics 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1386} PROGRAMMING T
49634 LCM Problem constructive algorithms greedy math number theory Statement A Educational Codeforces Round 92 (Rated for Div. 2) {1389} PROGRAMMING 80809
1921 Pairs of Pairs constructive algorithms dfs and similar graphs trees Statement E Codeforces Round 663 (Div. 2) {1391} PROGRAMMING 2750.0 Codeforces Round #663 (Div. 2) Editorial
25049 Suborrays constructive algorithms math Statement A Codeforces Round 663 (Div. 2) {1391} PROGRAMMING 500.0 Codeforces Round #663 (Div. 2) Editorial
2391 Omkar and Landslide binary search constructive algorithms greedy math Statement F Codeforces Global Round 10 {1392} PROGRAMMING 2500.0 Codeforces Global Round 10 — Editorial
3736 Omkar and Duck bitmasks constructive algorithms interactive math Statement E Codeforces Global Round 10 {1392} PROGRAMMING 2000.0 Codeforces Global Round 10 — Editorial
9747 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
11042 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
433 Distance Matching binary search constructive algorithms dfs and similar trees Statement E Codeforces Round 666 (Div. 1) {1396} PROGRAMMING 2500.0 Codeforces Round #666 — Editorial
12891 Stoned Game brute force constructive algorithms games greedy Statement B Codeforces Round 666 (Div. 1) {1396} PROGRAMMING 1000.0 Codeforces Round #666 — Editorial
16660 Multiples of Length constructive algorithms greedy number theory Statement A Codeforces Round 666 (Div. 1) {1396} PROGRAMMING 500.0 Codeforces Round #666 — Editorial
19871 Binary String To Subsequences constructive algorithms data structures greedy Statement D Codeforces Round 661 (Div. 3) {1399} PROGRAMMING Codeforces Round #661 (Div. 3) Editorial
18475 Binary String Reconstruction 2-sat constructive algorithms greedy strings Statement C Educational Codeforces Round 94 (Rated for Div. 2) {1400} PROGRAMMING 81942
27940 String Similarity brute force constructive algorithms strings Statement A Educational Codeforces Round 94 (Rated for Div. 2) {1400} PROGRAMMING 81942
10501 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
21762 Ternary Sequence constructive algorithms greedy math Statement B Codeforces Round 665 (Div. 2) {1401} PROGRAMMING 1000.0 Codeforces Round #665 (Div. 2) Editorial
26749 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
1269 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
11721 Link Cut Centroids constructive algorithms dfs and similar graphs trees Statement C Codeforces Round 670 (Div. 2) {1406} PROGRAMMING 1500.0 Codeforces Round #670 (Div. 2) Editorial
1885 Egor in the Republic of Dagestan constructive algorithms dfs and similar dp graphs greedy shortest paths Statement E Codeforces Round 669 (Div. 2) {1407} PROGRAMMING 2500.0 Codeforces Round #669 Editorial
14616 Chocolate Bunny constructive algorithms interactive math two pointers Statement C Codeforces Round 669 (Div. 2) {1407} PROGRAMMING 1500.0 Codeforces Round #669 Editorial
21343 Ahahahahahahahaha constructive algorithms math Statement A Codeforces Round 669 (Div. 2) {1407} PROGRAMMING 500.0 Codeforces Round #669 Editorial
2675 Two Different bitmasks constructive algorithms divide and conquer greedy Statement F Grakn Forces 2020 {1408} PROGRAMMING 2500.0 Grakn Forces -- Editorial
10443 Arrays Sum constructive algorithms greedy math Statement B Grakn Forces 2020 {1408} PROGRAMMING 1000.0 Grakn Forces -- Editorial