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1001 Beautiful Matrix combinatorics data structures dp Statement G Technocup 2019 - Elimination Round 4 {1085} PROGRAMMING Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial 2600
7539 New Year and the Permutation Concatenation combinatorics dp math Statement D Good Bye 2018 {1091} PROGRAMMING Editorial 1700
11850 Substring Removal combinatorics math strings Statement B Educational Codeforces Round 57 (Rated for Div. 2) {1096} PROGRAMMING Разбор Educational Codeforces Round 57 1400
1344 The Top Scorer combinatorics dp math probabilities Statement E Educational Codeforces Round 57 (Rated for Div. 2) {1096} PROGRAMMING Разбор Educational Codeforces Round 57 2600
1511 Alex and a TV Show bitmasks combinatorics number theory Statement F Hello 2019 {1097} PROGRAMMING 64310 2400
1126 Vladislav and a Great Legend combinatorics dp trees Statement G Hello 2019 {1097} PROGRAMMING 64310 2900
7045 Monotonic Renumeration combinatorics sortings Statement E Codeforces Round 531 (Div. 3) {1102} PROGRAMMING 64439 1800
11553 Ayoub and Lost Array combinatorics dp math Statement C Codeforces Round 533 (Div. 2) {1105} PROGRAMMING Tutorial 1500
1535 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
1184 Destroy the Colony combinatorics dp math Statement D CodeCraft-19 and Codeforces Round 537 (Div. 2) {1111} PROGRAMMING CodeCraft-19 and Codeforces Round #537 (Div. 2) Editorial 2500
673 Tree Cutting (Hard Version) combinatorics dfs and similar dp trees Statement F2 Codeforces Round 540 (Div. 3) {1118} PROGRAMMING 65396 2700
2144 Palindrome-less Arrays combinatorics divide and conquer dp Statement E Educational Codeforces Round 62 (Rated for Div. 2) {1140} PROGRAMMING Educational Codeforces Round 62 Editorial 2200
3824 Number of Components combinatorics data structures dp math Statement E Codeforces Round 553 (Div. 2) {1151} PROGRAMMING Codeforces Round #553 (Div. 2) Editorial 2100
1508 Sonya and Informatics combinatorics dp matrices probabilities Statement F Codeforces Round 553 (Div. 2) {1151} PROGRAMMING Codeforces Round #553 (Div. 2) Editorial 2500
965 Serval and Bonus Problem combinatorics dp math probabilities Statement F Codeforces Round 551 (Div. 2) {1153} PROGRAMMING Editorial 2800
15153 Silent Classroom combinatorics greedy Statement A Codeforces Round 561 (Div. 2) {1166} PROGRAMMING Codeforces Round #561 (Div. 2) Editorial 900
2957 Range Deleting binary search combinatorics data structures two pointers Statement E Educational Codeforces Round 65 (Rated for Div. 2) {1167} PROGRAMMING 67058 2100
1914 Scalar Queries combinatorics data structures math sortings Statement F Educational Codeforces Round 65 (Rated for Div. 2) {1167} PROGRAMMING 67058 2300
4448 Nauuo and Circle combinatorics dfs and similar dp trees Statement B Codeforces Round 564 (Div. 1) {1172} PROGRAMMING Codeforces Round #564 Editorial 2000
1821 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
13375 Tiles combinatorics greedy math Statement C Codeforces Global Round 4 {1178} PROGRAMMING E 1300
2322 Short Colorful Strip combinatorics dfs and similar dp Statement F1 Codeforces Global Round 4 {1178} PROGRAMMING E 2200
3411 Flag brute force combinatorics dp implementation Statement C Codeforces Round 567 (Div. 2) {1181} PROGRAMMING Editorial of Codeforces Round #567 (based on All-Russian olympiad in the name of Keldysh) 1900
3249 Playlist for Polycarp (easy version) bitmasks combinatorics dp Statement G1 Codeforces Round 568 (Div. 2) {1185} PROGRAMMING Editorial for Codeforces Round #568 (Div. 2) 2100
963 Playlist for Polycarp (hard version) combinatorics dp Statement G2 Codeforces Round 568 (Div. 2) {1185} PROGRAMMING Editorial for Codeforces Round #568 (Div. 2) 2800
299 Problem from Red Panda combinatorics Statement E Codeforces Round 572 (Div. 1) {1188} PROGRAMMING Editorial of Codeforces Round #572 3200
1241 Crossword Expert combinatorics dp number theory probabilities two pointers Statement F Educational Codeforces Round 68 (Rated for Div. 2) {1194} PROGRAMMING Разбор Educational Codeforces Round 68 2500
8226 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
4915 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
1886 Culture Code binary search combinatorics data structures dp shortest paths sortings Statement E Educational Codeforces Round 69 (Rated for Div. 2) {1197} PROGRAMMING E 2300
5486 Print a 1337-string... combinatorics constructive algorithms math strings Statement D Educational Codeforces Round 70 (Rated for Div. 2) {1202} PROGRAMMING 68972 1900
2156 Natasha, Sasha and the Prefix Sums combinatorics dp math number theory Statement E Codeforces Round 581 (Div. 2) {1204} PROGRAMMING 69244 2400
437 Expected Value Again combinatorics strings Statement E Codeforces Round 580 (Div. 1) {1205} PROGRAMMING 69158 3100
6750 Number Of Permutations combinatorics Statement D Educational Codeforces Round 71 (Rated for Div. 2) {1207} PROGRAMMING Educational Codeforces Round 71 Editorial 1800
19190 The Number of Products combinatorics dp implementation Statement B Codeforces Round 585 (Div. 2) {1215} PROGRAMMING Codeforces Round #585 Editorial 1500
943 Graph And Numbers bitmasks brute force combinatorics dp meet-in-the-middle Statement G Educational Codeforces Round 73 (Rated for Div. 2) {1221} PROGRAMMING Разбор Educational Codeforces Round 73 2900
1963 Wrong Answer on test 233 (Hard Version) combinatorics math Statement F2 Technocup 2020 - Elimination Round 3 {1227} PROGRAMMING Разбор задач №2 2400
3571 Another Filling the Grid combinatorics dp math Statement E Codeforces Round 589 (Div. 2) {1228} PROGRAMMING 70162 2300
12146 Alice and the List of Presents combinatorics math Statement B Codeforces Round 593 (Div. 2) {1236} PROGRAMMING 70654 1400
1153 Balanced Domino Placements combinatorics dp Statement F Codeforces Global Round 5 {1237} PROGRAMMING T 2600
6463 AB-string binary search combinatorics dp strings Statement D Educational Codeforces Round 74 (Rated for Div. 2) {1238} PROGRAMMING Educational Codeforces Round 74 Editorial 1800
7812 Ivan the Fool and the Probability Theory combinatorics dp math Statement A Codeforces Round 594 (Div. 1) {1239} PROGRAMMING Editorial of Codeforces Round #594 (on the problems of Moscow Team Olympiad) 1700
2303 Daniel and Spring Cleaning bitmasks brute force combinatorics dp Statement F Codeforces Round 597 (Div. 2) {1245} PROGRAMMING Codeforces Round #597 (Div. 2) Editorial 2300
1035 Red-White Fence combinatorics fft Statement F Educational Codeforces Round 75 (Rated for Div. 2) {1251} PROGRAMMING 70860 2600
422 Send Tree to Charlie combinatorics dfs and similar dsu trees Statement E Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 3200
1579 Beautiful Bracket Sequence (easy version) combinatorics dp probabilities Statement D1 Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 2600
1397 Beautiful Bracket Sequence (hard version) combinatorics probabilities Statement D2 Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 3000
2169 Key Storage combinatorics math Statement K 2019-2020 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1267} PROGRAMMING nerc-2019-tutorial.pdf 2200
3795 Common Number binary search combinatorics dp math Statement E Codeforces Round 608 (Div. 2) {1271} PROGRAMMING 72247 2100
31257 Yet Another Broken Keyboard combinatorics dp implementation Statement C Codeforces Round 605 (Div. 3) {1272} PROGRAMMING Codeforces Round #605 (Div. 3) Editorial 1100
5731 Two Fairs combinatorics dfs and similar dsu graphs Statement B Codeforces Round 606 (Div. 1, based on Technocup 2020 Elimination Round 4) {1276} PROGRAMMING Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial 1900
1794 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
2681 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
7448 Santa's Bot combinatorics math probabilities Statement D Educational Codeforces Round 79 (Rated for Div. 2) {1279} PROGRAMMING Educational Codeforces Round 79 Editorial 1700
481 New Year Permutations combinatorics dp Statement E Educational Codeforces Round 79 (Rated for Div. 2) {1279} PROGRAMMING Educational Codeforces Round 79 Editorial 2700
113 Intergalactic Sliding Puzzle combinatorics constructive algorithms math Statement F Codeforces Round 607 (Div. 1) {1280} PROGRAMMING Codeforces Round #607 Editorial 3400
11571 New Year and Ascent Sequence binary search combinatorics data structures dp implementation sortings Statement B Hello 2020 {1284} PROGRAMMING Hello 2020 Editorial 1500
8791 New Year and Permutation combinatorics math Statement C Hello 2020 {1284} PROGRAMMING Hello 2020 Editorial 1700
1414 New Year and Castle Construction combinatorics geometry math sortings Statement E Hello 2020 {1284} PROGRAMMING Hello 2020 Editorial 2500
1390 Classical? binary search combinatorics number theory Statement F Codeforces Round 613 (Div. 2) {1285} PROGRAMMING Codeforces Round #613 (Div. 2) Editorial 2800
15656 Two Arrays combinatorics dp Statement C Educational Codeforces Round 80 (Rated for Div. 2) {1288} PROGRAMMING Educational Codeforces Round 80 Editorial 1600
2328 Xenon's Attack on the Gangs combinatorics dfs and similar dp greedy trees Statement C Codeforces Round 614 (Div. 1) {1292} PROGRAMMING 1250.0 Codeforces Round #614 Editorial 2300
418 Nora's Toy Boxes bitmasks combinatorics dp Statement F Codeforces Round 614 (Div. 1) {1292} PROGRAMMING 2750.0 Codeforces Round #614 Editorial 3400
22397 JOE is on TV! combinatorics greedy math Statement B Codeforces Round 614 (Div. 2) {1293} PROGRAMMING 750.0 Codeforces Round #614 Editorial 1000
1552 Good Contest combinatorics dp probabilities Statement F Educational Codeforces Round 81 (Rated for Div. 2) {1295} PROGRAMMING Educational Codeforces Round 81 Editorial 2600
615 Around the World bitmasks combinatorics dfs and similar dp graphs graphs math trees Statement D Codeforces Round 618 (Div. 1) {1299} PROGRAMMING 1750.0 Codeforces Round #618 Editorial 2900
9950 Ayoub's function binary search combinatorics greedy math strings Statement C Codeforces Round 619 (Div. 2) {1301} PROGRAMMING 1250.0 Codeforces Round #619 (Div. 2) Editorial 1700
19576 Kuroni and Impossible Calculation brute force combinatorics math number theory Statement C Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} PROGRAMMING 1250.0 Ozon Tech Challenge 2020 Editorial 1600
1422 Cow and Treats binary search combinatorics dp greedy implementation math Statement E Codeforces Round 621 (Div. 1 + Div. 2) {1307} PROGRAMMING 2500.0 Codeforces Round #621 (Div. 1 + Div. 2) Editorial 2400
10707 Count the Arrays combinatorics math Statement D Educational Codeforces Round 83 (Rated for Div. 2) {1312} PROGRAMMING 74640
16535 Permutation Partitions combinatorics greedy math Statement C Codeforces Global Round 7 {1326} PROGRAMMING 1000.0 74961 1300
9769 Count The Blocks combinatorics dp math Statement E Educational Codeforces Round 84 (Rated for Div. 2) {1327} PROGRAMMING Educational Codeforces Round 84 Editorial 1800
2107 AND Segments bitmasks combinatorics data structures dp two pointers Statement F Educational Codeforces Round 84 (Rated for Div. 2) {1327} PROGRAMMING Educational Codeforces Round 84 Editorial 2500
32390 K-th Beautiful String combinatorics implementation math Statement B Codeforces Round 629 (Div. 3) {1328} PROGRAMMING 75246 1300
7182 Dreamoon Likes Sequences bitmasks combinatorics dp math Statement B Codeforces Round 631 (Div. 1) - Thanks, Denis aramis Shitov! {1329} PROGRAMMING 750.0 Codeforces Round #631 Editorial 1900
4369 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
3219 Divisor Paths combinatorics graphs greedy math number theory Statement E Educational Codeforces Round 85 (Rated for Div. 2) {1334} PROGRAMMING Educational Codeforces Round 85 Editorial
883 Chiori and Doll Picking (easy version) bitmasks brute force combinatorics math Statement E1 Codeforces Round 635 (Div. 1) {1336} PROGRAMMING 1750.0 Codeforces Round #635 Editorial 2600
605 Chiori and Doll Picking (hard version) bitmasks brute force combinatorics math Statement E2 Codeforces Round 635 (Div. 1) {1336} PROGRAMMING 1500.0 Codeforces Round #635 Editorial 3400
3664 Placing Rooks combinatorics fft math Statement E Educational Codeforces Round 86 (Rated for Div. 2) {1342} PROGRAMMING 76633 2300
6829 Modular Stability combinatorics math number theory Statement E Educational Codeforces Round 88 (Rated for Div. 2) {1359} PROGRAMMING Educational Codeforces Round 88 Editorial 2000
1462 Secure Password bitmasks combinatorics constructive algorithms interactive math Statement G Codeforces Round 648 (Div. 2) {1365} PROGRAMMING 3000.0 Editorial — Codeforces Round #648 2800
4664 Two Arrays binary search brute force combinatorics dp greedy implementation two pointers Statement E Educational Codeforces Round 89 (Rated for Div. 2) {1366} PROGRAMMING Educational Codeforces Round 89 Editorial
5543 Asterism (Easy Version) brute force combinatorics implementation math number theory sortings Statement E1 Codeforces Round 654 (Div. 2) {1371} PROGRAMMING 1500.0 Codeforces Round #654 (Div. 2) Editorial
9667 Unmerge combinatorics dp two pointers Statement B Codeforces Round 658 (Div. 1) {1381} PROGRAMMING 1500.0 Codeforces Round #658 Editorial 1800
16124 Cyclic Permutations combinatorics graphs math Statement C Codeforces Round 663 (Div. 2) {1391} PROGRAMMING 1250.0 Codeforces Round #663 (Div. 2) Editorial
1069 ZS Shuffles Cards combinatorics math probabilities Statement H Codeforces Global Round 10 {1392} PROGRAMMING 3500.0 Codeforces Global Round 10 — Editorial
1195 Mercenaries bitmasks combinatorics data structures math two pointers Statement G Educational Codeforces Round 94 (Rated for Div. 2) {1400} PROGRAMMING 81942
268 Star Trek *special combinatorics dfs and similar dp games graphs matrices trees Statement C Central-European Olympiad in Informatics, CEOI 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1402} PROGRAMMING Editorial
94 Chess Rush *special combinatorics dp implementation math Statement C Central-European Olympiad in Informatics, CEOI 2020, Day 2 (IOI, Unofficial Mirror Contest, Unrated) {1403} PROGRAMMING CEOI 2020 Online Mirror — Day 2 Tutorial
1370 Clusterization Counting combinatorics dp dsu fft graphs Statement G Grakn Forces 2020 {1408} PROGRAMMING 3000.0 Grakn Forces -- Editorial
2287 Expected Damage binary search combinatorics math probabilities Statement E Educational Codeforces Round 95 (Rated for Div. 2) {1418} PROGRAMMING Unofficial Editorial for Educational Round 95 (Div. 2)
8420 Rescue Nibel! combinatorics data structures sortings Statement D Codeforces Round 672 (Div. 2) {1420} PROGRAMMING 2000.0 Editorial
917 Danger of Mad Snakes combinatorics dp math Statement D 2020 ICPC, COMPFEST 12, Indonesia Multi-Provincial Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1425} PROGRAMMING Tutorial 2300
6275 Number of Subsequences combinatorics dp strings Statement F Codeforces Round 674 (Div. 3) {1426} PROGRAMMING 83120 2000
20000 Two Round Dances combinatorics math Statement E Codeforces Round 677 (Div. 3) {1433} PROGRAMMING Codeforces Round #677 (Div. 3) Editorial
11810 Binary Search binary search combinatorics Statement C Codeforces Round 678 (Div. 2) {1436} PROGRAMMING 1500.0 Codeforces Round #678 (Div. 2). Editorial
668 Sum Over Subsets combinatorics math number theory Statement F Codeforces Round 678 (Div. 2) {1436} PROGRAMMING 3000.0 Codeforces Round #678 (Div. 2). Editorial
1658 Emotional Fishermen combinatorics dp math Statement F Educational Codeforces Round 97 (Rated for Div. 2) {1437} PROGRAMMING 84149
538 INOI Final Contests combinatorics dp Statement D Codeforces Round 684 (Div. 1) {1439} PROGRAMMING 2500.0 Codeforces Round #684[Div1 and Div2] Editorial
5409 Identify the Operations brute force combinatorics data structures dsu greedy implementation Statement B Codeforces Round 681 (Div. 1, based on VK Cup 2019-2020 - Final) {1442} PROGRAMMING 1000.0 84298
1580 Long Permutation brute force combinatorics math Statement E Codeforces Round 681 (Div. 2, based on VK Cup 2019-2020 - Final) {1443} PROGRAMMING 2500.0 VK Cup 2019-2020 -- Engine Editorial
6819 Divide and Sum combinatorics math Statement B Codeforces Round 680 (Div. 1, based on Moscow Team Olympiad) {1444} PROGRAMMING 1000.0 Codeforces Round #680 Editorial
565 Multithreading (Easy Version) combinatorics fft math Statement H1 Codeforces Global Round 12 {1450} PROGRAMMING 2750.0 Codeforces Global Round 12 Editorial
324 Multithreading (Hard Version) combinatorics implementation math Statement H2 Codeforces Global Round 12 {1450} PROGRAMMING 1750.0 Codeforces Global Round 12 Editorial
8776 Radio Towers combinatorics dp math Statement D Educational Codeforces Round 98 (Rated for Div. 2) {1452} PROGRAMMING 84847
6776 Number of Simple Paths combinatorics data structures dfs and similar dsu graphs trees Statement E Codeforces Round 686 (Div. 3) {1454} PROGRAMMING Codeforces Round #686 (Div. 3) Editorial
11575 Close Tuples (hard version) binary search combinatorics implementation math sortings two pointers Statement E2 Codeforces Round 690 (Div. 3) {1462} PROGRAMMING Codeforces Round #690 (Div. 3) Editorial
15369 Close Tuples (easy version) binary search combinatorics math sortings two pointers Statement E1 Codeforces Round 690 (Div. 3) {1462} PROGRAMMING Codeforces Round #690 (Div. 3) Editorial
4055 Sum of Paths combinatorics dp math Statement D Codeforces Round 695 (Div. 2) {1467} PROGRAMMING 1750.0 Codeforces Round #695 (Div. 2) Editorial 2200
927 Strange Permutation binary search combinatorics data structures dp two pointers Statement E Codeforces Round 694 (Div. 1) {1470} PROGRAMMING 2000.0 86464
483 Tiles combinatorics dp fft math Statement G Educational Codeforces Round 102 (Rated for Div. 2) {1473} PROGRAMMING Educational Codeforces Round 102 Editorial
28127 Ball in Berland combinatorics dfs and similar graphs hashing math Statement C Codeforces Round 697 (Div. 3) {1475} PROGRAMMING Codeforces Round #697 (Div. 3) Editorial
18342 Advertising Agency combinatorics implementation math sortings Statement E Codeforces Round 697 (Div. 3) {1475} PROGRAMMING Codeforces Round #697 (Div. 3) Editorial
336 Nezzar and Chocolate Bars combinatorics fft math probabilities Statement F Codeforces Round 698 (Div. 1) {1477} PROGRAMMING 4000.0 87294 3500
2370 Copy or Prefix Sum combinatorics data structures dp sortings Statement F Codeforces Round 701 (Div. 2) {1485} PROGRAMMING 3000.0 Editorial of Codeforces Round #701 (Div. 2) 2400
842 Pairs of Paths combinatorics data structures trees Statement F Codeforces Round 703 (Div. 2) {1486} PROGRAMMING 3000.0 Codeforces Round #703 (Div. 2) Editorial
732 String Counting combinatorics dp math Statement G Educational Codeforces Round 104 (Rated for Div. 2) {1487} PROGRAMMING 87873
74 Build From Suffixes *special combinatorics data structures Statement H Kotlin Heroes: Episode 6 {1488} PROGRAMMING 88522
1581 BFS Trees combinatorics dfs and similar graphs math shortest paths trees Statement D Codeforces Round 706 (Div. 1) {1495} PROGRAMMING 2000.0 Codeforces Round #706 Editorial
12488 Planar Reflections brute force combinatorics data structures dp Statement C CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} PROGRAMMING 1750.0 CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial
2160 Two Houses brute force combinatorics graphs interactive probabilities sortings Statement E CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} PROGRAMMING 2500.0 CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial
1691 Chaotic Merge combinatorics dp Statement E Educational Codeforces Round 106 (Rated for Div. 2) {1499} PROGRAMMING Educational Codeforces Round 106 Editorial
906 2-Coloring combinatorics dp math Statement E Codeforces Round 712 (Div. 1) {1503} PROGRAMMING 2500.0 T 3100
4489 Almost Sorted binary search bitmasks combinatorics constructive algorithms dp implementation math Statement B Codeforces Round 715 (Div. 1) {1508} PROGRAMMING 1000.0 Codeforces Round #715 Editorial
2932 Colorings and Dominoes combinatorics dp math Statement E Educational Codeforces Round 107 (Rated for Div. 2) {1511} PROGRAMMING 89634
20857 AND Sequences bitmasks combinatorics constructive algorithms Statement B Divide by Zero 2021 and Codeforces Round 714 (Div. 2) {1513} PROGRAMMING 1250.0 Divide by Zero 2021 and Codeforces Round #714 (Div. 2) Editorial
1759 Cost Equilibrium combinatorics constructive algorithms math sortings Statement E Divide by Zero 2021 and Codeforces Round 714 (Div. 2) {1513} PROGRAMMING 2750.0 Divide by Zero 2021 and Codeforces Round #714 (Div. 2) Editorial
36468 AND 0, Sum Big bitmasks combinatorics math Statement B Codeforces Round 716 (Div. 2) {1514} PROGRAMMING 1000.0 Codeforces round #716 editorial
4606 Phoenix and Computers combinatorics dp math Statement E Codeforces Global Round 14 {1515} PROGRAMMING 2750.0 Editorial
1059 Baby Ehab Plays with Permutations combinatorics dp math Statement E Codeforces Round 717 (Div. 2) {1516} PROGRAMMING 2750.0 Codeforces round #717 editorial
1057 Group Photo binary search combinatorics implementation two pointers Statement E Contest 2050 and Codeforces Round 718 (Div. 1 + Div. 2) {1517} PROGRAMMING 2500.0 Contest 2050 and Codeforces Round #718 (Div.1 + Div.2) Editorial
1985 Crypto Lights combinatorics dp probabilities Statement E Deltix Round, Spring 2021 (open for everyone, rated, Div. 1 + Div. 2) {1523} PROGRAMMING 2250.0 Deltix Round, Spring 2021. Editorial 2600
2519 Assimilation IV combinatorics dp math probabilities Statement E Educational Codeforces Round 109 (Rated for Div. 2) {1525} PROGRAMMING 90793
1531 Oolimry and Suffix Array combinatorics constructive algorithms math string suffix structures Statement E Codeforces Round 723 (Div. 2) {1526} PROGRAMMING 2500.0 Codeforces Round #723 (Div. 2) Editorial
2332 MEX Tree combinatorics constructive algorithms data structures dfs and similar math trees Statement D Codeforces Round 721 (Div. 2) {1527} PROGRAMMING 2250.0 Tutorial 2400
634 Mashtali and Hagh Trees combinatorics dp trees Statement E Codeforces Round 722 (Div. 1) {1528} PROGRAMMING 2750.0 Codeforces Round #722 Editorial
487 AmShZ Farm combinatorics fft math Statement F Codeforces Round 722 (Div. 1) {1528} PROGRAMMING 3000.0 Codeforces Round #722 Editorial
13976 Little Alawn's Puzzle combinatorics dfs and similar dp dsu graphs math Statement C Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) {1534} PROGRAMMING 1250.0 Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) Editorial
2761 Omkar and Forest combinatorics graphs math shortest paths Statement E Codeforces Round 724 (Div. 2) {1536} PROGRAMMING 2250.0 Codeforces Round #724 — Editorial 2300
1179 Omkar and Akmar combinatorics games math Statement F Codeforces Round 724 (Div. 2) {1536} PROGRAMMING 2500.0 Codeforces Round #724 — Editorial 2600
21687 Contest Start combinatorics geometry math Statement A Codeforces Round 727 (Div. 2) {1539} PROGRAMMING 500.0 tutorial 1000
3063 Tree Array brute force combinatorics dp math probabilities trees Statement B Codeforces Round 728 (Div. 1) {1540} PROGRAMMING 1250.0 Tutorial
1478 Abnormal Permutation Pairs (easy version) combinatorics dp fft math Statement E1 Codeforces Round 729 (Div. 2) {1542} PROGRAMMING 2000.0
2999 Priority Queue combinatorics dp implementation math Statement D Codeforces Round 729 (Div. 2) {1542} PROGRAMMING 2000.0
1062 Abnormal Permutation Pairs (hard version) combinatorics dp math Statement E2 Codeforces Round 729 (Div. 2) {1542} PROGRAMMING 1000.0
24627 Customising the Track combinatorics greedy math Statement B Codeforces Round 730 (Div. 2) {1543} PROGRAMMING 750.0 Codeforces Round #730 (Div. 2) Editorial
6887 AquaMoon and Chess combinatorics math Statement B Codeforces Round 732 (Div. 1) {1545} PROGRAMMING 1000.0 Codeforces Round #732 Editorial 1900
791 AquaMoon and Permutations combinatorics constructive algorithms graph matchings graphs Statement C Codeforces Round 732 (Div. 1) {1545} PROGRAMMING 1500.0 Codeforces Round #732 Editorial 2800
2103 The Three Little Pigs combinatorics dp fft math Statement C Codeforces Round 736 (Div. 1) {1548} PROGRAMMING 1750.0 Codeforces Round 736 Editorial
2088 Excellent Arrays brute force combinatorics constructive algorithms implementation math Statement D Educational Codeforces Round 111 (Rated for Div. 2) {1550} PROGRAMMING Educational Codeforces Round 111 Editorial
2225 Equidistant Vertices combinatorics dfs and similar dp trees Statement F Codeforces Round 734 (Div. 3) {1551} PROGRAMMING Editorial for Codeforces Round #734 (Div.3)
6325 Maximize the Intersections combinatorics constructive algorithms geometry greedy Statement C Codeforces Global Round 15 {1552} PROGRAMMING 1000.0 Editorial of Global Round 15
17071 Running for Gold combinatorics graphs greedy probabilities sortings Statement B Codeforces Global Round 15 {1552} PROGRAMMING 500.0 Editorial of Global Round 15
3830 Permutation Shift brute force combinatorics constructive algorithms dfs and similar graphs math Statement E Harbour.Space Scholarship Contest 2021-2022 (open for everyone, rated, Div. 1 + Div. 2) {1553} PROGRAMMING 1750.0 Harbour.Space Scholarship Contest 2021-2022 (Div. 1 + Div. 2) Editorial
343 Stairs combinatorics divide and conquer fft math Statement I Harbour.Space Scholarship Contest 2021-2022 (open for everyone, rated, Div. 1 + Div. 2) {1553} PROGRAMMING 5250.0 Harbour.Space Scholarship Contest 2021-2022 (Div. 1 + Div. 2) Editorial
1457 Sports Betting bitmasks combinatorics dp graphs math probabilities Statement F Deltix Round, Summer 2021 (open for everyone, rated, Div. 1 + Div. 2) {1556} PROGRAMMING 2500.0 94384 2500
10878 Moamen and XOR bitmasks combinatorics dp math Statement C Codeforces Round 737 (Div. 2) {1557} PROGRAMMING 1750.0 Codeforces Round #737 Editorial
1168 Top-Notch Insertions combinatorics data structures Statement D Codeforces Round 740 (Div. 1, based on VK Cup 2021 - Final (Engine)) {1558} PROGRAMMING 2000.0 Codeforces Round #740 Editorial 2600
2785 Mocha and Stars combinatorics dp fft math number theory Statement E Codeforces Round 738 (Div. 2) {1559} PROGRAMMING 3000.0 Tutorial (en) 2200
13268 Carrying Conundrum bitmasks combinatorics dp Statement C Codeforces Round 742 (Div. 2) {1567} PROGRAMMING 1500.0 Codeforces Round #742 Editorial
13440 Jury Meeting combinatorics math Statement C Educational Codeforces Round 113 (Rated for Div. 2) {1569} PROGRAMMING 94721
1087 Coloring combinatorics constructive algorithms implementation Statement E Educational Codeforces Round 114 (Rated for Div. 2) {1574} PROGRAMMING 95188
773 Occurrences combinatorics dp dsu fft graphs Statement F Educational Codeforces Round 114 (Rated for Div. 2) {1574} PROGRAMMING 95188
18282 Combinatorics Homework combinatorics greedy math Statement B Educational Codeforces Round 114 (Rated for Div. 2) {1574} PROGRAMMING 95188
1344 Mathematics Curriculum combinatorics dp trees Statement B Codeforces Round 745 (Div. 1) {1580} PROGRAMMING 1000.0 Codeforces Round #745 Editorial 2600
35465 Luntik and Subsequences combinatorics math Statement B Codeforces Round 750 (Div. 2) {1582} PROGRAMMING 750.0 Codeforces Round #750 (Div.2) Editorial
4026 Guess the Permutation binary search combinatorics interactive math Statement D Technocup 2022 - Elimination Round 2 {1584} PROGRAMMING 1500.0 Editorial for Technocup 2022 — Elimination Round 2 and Codeforces Round #755 (Div. 1, Div. 2) 2000
1729 Non-equal Neighbours combinatorics dp math Statement F Technocup 2022 - Elimination Round 3 {1585} PROGRAMMING 3000.0 Codeforces Round #759 (Div. 2, based on Technocup 2022 Elimination Round 3) Editorial
339 Omkar and Mosaic combinatorics constructive algorithms math Statement I Codeforces Round 749 (Div. 1 + Div. 2, based on Technocup 2022 Elimination Round 1) {1586} PROGRAMMING 4000.0 Editorial for Technocup 2022 — Elimination Round 1 and Codeforces Round #749 (Div. 1+Div. 2)
336 Non-equal Neighbours combinatorics data structures dp math Statement F Codeforces Round 759 (Div. 2, based on Technocup 2022 Elimination Round 3) {1591} PROGRAMMING 3000.0 Codeforces Round #759 (Div. 2, based on Technocup 2022 Elimination Round 3) Editorial
12390 Rubik's Cube Coloring (easy version) combinatorics math Statement E1 Codeforces Round 747 (Div. 2) {1594} PROGRAMMING 1000.0 95525 1300
2535 Staircases brute force combinatorics data structures dfs and similar dp Statement E Educational Codeforces Round 115 (Rated for Div. 2) {1598} PROGRAMMING 95890
10717 Training Session combinatorics math Statement D Educational Codeforces Round 115 (Rated for Div. 2) {1598} PROGRAMMING 95890
2039 Bubble Strike combinatorics math probabilities ternary search Statement C Bubble Cup 14 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred, Div. 1) {1599} PROGRAMMING BubbleCup2021.pdf
668 A Perfect Problem combinatorics dp Statement E Codeforces Round 752 (Div. 1) {1603} PROGRAMMING 3500.0 Editorial of Codeforces Round #752
388 October 18, 2017 combinatorics dp implementation math Statement F Codeforces Round 752 (Div. 1) {1603} PROGRAMMING 3750.0 Editorial of Codeforces Round #752
436 PalindORme combinatorics dp Statement F Codeforces Round 754 (Div. 2) {1605} PROGRAMMING 3500.0 tutorial 2900
4275 Arena combinatorics dp Statement E Educational Codeforces Round 116 (Rated for Div. 2) {1606} PROGRAMMING 96454
908 MEX counting combinatorics dp Statement F Codeforces Round 758 (Div.1 + Div. 2) {1608} PROGRAMMING 2500.0 Editorial of Codeforces Round #758 (Div.1 + Div. 2)
1590 Dominoes combinatorics fft graphs math Statement D Codeforces Round 758 (Div.1 + Div. 2) {1608} PROGRAMMING 1500.0 Editorial of Codeforces Round #758 (Div.1 + Div. 2)
3085 Not Quite Lee combinatorics math number theory Statement D Codeforces Global Round 17 {1610} PROGRAMMING 2250.0 Codeforces Global Round 17 Editorial
1030 Max Sum Array combinatorics constructive algorithms greedy sortings Statement G Educational Codeforces Round 117 (Rated for Div. 2) {1612} PROGRAMMING 97164
874 Tree Coloring combinatorics fft Statement F Educational Codeforces Round 118 (Rated for Div. 2) {1613} PROGRAMMING 97467
11397 Divan and bitwise operations bitmasks combinatorics constructive algorithms dp math Statement C Codeforces Round 757 (Div. 2) {1614} PROGRAMMING 1500.0 Tutorial 1500
1179 LEGOndary Grandmaster combinatorics dp math Statement F Codeforces Global Round 18 {1615} PROGRAMMING 3000.0 Global Round 18 Editorial
1309 Keep XOR Low bitmasks combinatorics divide and conquer dp math Statement H Good Bye 2021: 2022 is NEAR {1616} PROGRAMMING 4000.0 Good Bye 2021 -- Editorial 3000
1194 Subsequences Galore bitmasks combinatorics dp math Statement G Educational Codeforces Round 119 (Rated for Div. 2) {1620} PROGRAMMING 98061
4762 Shuffle combinatorics math two pointers Statement D Educational Codeforces Round 120 (Rated for Div. 2) {1622} PROGRAMMING Educational Codeforces Round 120 Editorial
922 A Random Code Problem combinatorics dp math number theory Statement F Educational Codeforces Round 121 (Rated for Div. 2) {1626} PROGRAMMING 99136
3800 Game on Sum (Easy Version) combinatorics dp games Statement D1 Codeforces Round 767 (Div. 1) {1628} PROGRAMMING 1000.0 99276
2688 Game on Sum (Hard Version) combinatorics dp games Statement D2 Codeforces Round 767 (Div. 1) {1628} PROGRAMMING 750.0 99276
607 Expected Components combinatorics number theory probabilities Statement E Codeforces Round 768 (Div. 1) {1630} PROGRAMMING 2500.0 Editorial of Codeforces Round #768
1543 Two Arrays bitmasks brute force combinatorics hashing probabilities two pointers Statement D Codeforces Round 773 (Div. 1) {1641} PROGRAMMING 1750.0 Codeforces Round #773 editorial
338 Special Positions combinatorics fft Statement E Codeforces Round 773 (Div. 1) {1641} PROGRAMMING 2250.0 Codeforces Round #773 editorial
3503 Expand the Path brute force combinatorics implementation math Statement E Educational Codeforces Round 123 (Rated for Div. 2) {1644} PROGRAMMING 100227
482 Basis combinatorics fft math number theory Statement F Educational Codeforces Round 123 (Rated for Div. 2) {1644} PROGRAMMING 100227
19630 Weird Sum combinatorics data structures geometry math matrices sortings Statement A Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} PROGRAMMING 500.0 Codeforces Round #775 Editorial
3360 Tyler and Strings combinatorics data structures implementation strings Statement C Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} PROGRAMMING 1500.0 Codeforces Round #775 Editorial
108 Three Minimums combinatorics fft math Statement H Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} PROGRAMMING 4000.0 Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) 3500
2538 Star MST combinatorics dp math Statement E Educational Codeforces Round 125 (Rated for Div. 2) {1657} PROGRAMMING 101161
19579 Marin and Anti-coprime Permutation combinatorics math Statement B Codeforces Round 779 (Div. 2) {1658} PROGRAMMING 1000.0 Codeforces Round #779 (Div. 2) Editorial
1574 Fancy Stack combinatorics dp Statement F 2021-2022 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1666} PROGRAMMING Tutorial (PDF)
894 Centroid Probabilities combinatorics dp fft math Statement E Codeforces Round 783 (Div. 1) {1667} PROGRAMMING 2750.0 Codeforces Round #783 Editorial 3000
1310 Jee, You See? bitmasks combinatorics dp Statement F Codeforces Round 788 (Div. 2) {1670} PROGRAMMING 3000.0 Tutorial 2400
499 Permutation Counting brute force combinatorics dp fft math Statement F Educational Codeforces Round 127 (Rated for Div. 2) {1671} PROGRAMMING 102181
3312 Preorder combinatorics divide and conquer dp dsu hashing trees Statement E Educational Codeforces Round 127 (Rated for Div. 2) {1671} PROGRAMMING 102181
3643 Lost Arithmetic Progression combinatorics implementation math number theory Statement D Codeforces Round 785 (Div. 2) {1673} PROGRAMMING 2000.0 Codeforces Round #785 (Div. 2) Editorial
816 Power or XOR? combinatorics math number theory Statement E Codeforces Round 785 (Div. 2) {1673} PROGRAMMING 2750.0 Codeforces Round #785 (Div. 2) Editorial
26604 Infinite Replacement combinatorics implementation strings Statement C Codeforces Round 786 (Div. 3) {1674} PROGRAMMING 102482
29779 Dictionary combinatorics math Statement B Codeforces Round 786 (Div. 3) {1674} PROGRAMMING 102482
1445 Typical Party in Dorm bitmasks brute force combinatorics dp strings two pointers Statement E Codeforces Round 791 (Div. 2) {1679} PROGRAMMING 2250.0 Codeforces Round #791 (Div. 2) Editorial
320 Become Big For Me combinatorics constructive algorithms math number theory Statement E Codeforces Round 796 (Div. 1) {1687} PROGRAMMING 2000.0 Editorial of Codeforces Round 796
1168 K-Set Tree combinatorics dfs and similar dp math trees Statement F CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} PROGRAMMING 2750.0 Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2)
214 Maximum Product? brute force combinatorics dp greedy math two pointers Statement H Codeforces Global Round 21 {1696} PROGRAMMING 4000.0 Editorial of Codeforces Global Round 21
4996 Placing Jinas combinatorics math Statement E Codeforces Global Round 21 {1696} PROGRAMMING 2000.0 Editorial of Codeforces Global Round 21
1476 Coloring brute force combinatorics constructive algorithms dfs and similar dp dsu graphs implementation Statement E Educational Codeforces Round 130 (Rated for Div. 2) {1697} PROGRAMMING 103835
1860 PermutationForces II binary search brute force combinatorics constructive algorithms greedy sortings Statement E Codeforces Round 803 (Div. 2) {1698} PROGRAMMING 2000.0 Codeforces Round #803 (Div. 2) Editorial
10812 The Third Problem combinatorics math two pointers Statement C Codeforces Round 804 (Div. 2) {1699} PROGRAMMING 1500.0 Codeforces Round #804 (Div. 2) Editorial
1176 Points combinatorics data structures math matrices Statement F Educational Codeforces Round 131 (Rated for Div. 2) {1701} PROGRAMMING Educational Codeforces Round 131 Editorial
311 Game of AI (easy version) combinatorics fft math Statement H1 CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} PROGRAMMING 2250.0 CodeTON Round 2 Editorial
117 Game of AI (hard version) combinatorics fft math Statement H2 CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} PROGRAMMING 2750.0 CodeTON Round 2 Editorial
2504 Mark and Professor Koro binary search bitmasks combinatorics data structures greedy Statement E Codeforces Round 807 (Div. 2) {1705} PROGRAMMING 2500.0 Codeforces Round #807 (Div 2.) Editorial
7214 Mark and Lightbulbs combinatorics constructive algorithms math sortings Statement D Codeforces Round 807 (Div. 2) {1705} PROGRAMMING 1750.0 Codeforces Round #807 (Div 2.) Editorial
955 Partial Virtual Trees combinatorics dp math trees Statement D Codeforces Round 808 (Div. 1) {1707} PROGRAMMING 1750.0 104930
2523 LCM Sum (easy version) binary search brute force combinatorics math number theory two pointers Statement E1 Codeforces Round 813 (Div. 2) {1712} PROGRAMMING 2000.0 Codeforces Round #813 (Div. 2) Editorial
1658 LCM Sum (hard version) combinatorics data structures math number theory two pointers Statement E2 Codeforces Round 813 (Div. 2) {1712} PROGRAMMING 750.0 Codeforces Round #813 (Div. 2) Editorial
745 Lost Array bitmasks combinatorics constructive algorithms dp math Statement F Codeforces Round 812 (Div. 2) {1713} PROGRAMMING 3000.0 Codeforces Round #812 (Div. 2) Editorial 2900
10613 Monoblock brute force combinatorics data structures divide and conquer greedy implementation Statement C Codeforces Round 816 (Div. 2) {1715} PROGRAMMING 1750.0 Codeforces Round #816 (Div. 2) editorial
1451 Bags with Balls combinatorics math number theory Statement F Educational Codeforces Round 133 (Rated for Div. 2) {1716} PROGRAMMING 105653
4919 Madoka and The Corruption Scheme combinatorics math Statement D Codeforces Round 818 (Div. 2) {1717} PROGRAMMING 2000.0 Codeforces Round #818 (Div. 2) Editorial. 1900
1993 Circular Mirror binary search combinatorics math two pointers Statement C COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} PROGRAMMING Tutorial
622 Electrical Efficiency combinatorics data structures dp number theory trees Statement E COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} PROGRAMMING Tutorial
324 Imitating the Key Tree combinatorics dsu trees Statement I COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} PROGRAMMING Tutorial
1760 Almost Perfect combinatorics fft math Statement E Codeforces Round 819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 {1726} PROGRAMMING 2250.0 Codeforces Round #819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 Editorial
433 A Certain Magical Party combinatorics greedy sortings Statement G Codeforces Round 819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 {1726} PROGRAMMING 3250.0 Codeforces Round #819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 Editorial
655 Illumination combinatorics dp Statement G Educational Codeforces Round 135 (Rated for Div. 2) {1728} PROGRAMMING 106805
2588 Cut Substrings combinatorics dp hashing strings two pointers Statement G Codeforces Round 820 (Div. 3) {1729} PROGRAMMING Codeforces Round #820 (Div. 3) Editorial
804 Maximums and Minimums combinatorics combinatorics data structures number theory Statement E Codeforces Round 823 (Div. 2) {1730} PROGRAMMING 2250.0 Codeforces Round #823 — editorial 2700
910 Function Sum brute force combinatorics dp fft math Statement F Codeforces Round 841 (Div. 2) and Divide by Zero 2022 {1731} PROGRAMMING 2750.0 Codeforces Round #841 (Div. 2) and Divide By Zero 2022 Editorial
7059 Meta-set brute force combinatorics data structures hashing math Statement D Codeforces Round 824 (Div. 2) {1735} PROGRAMMING 1750.0 Codeforces Round #824 — editorial
1842 Balance Addicts combinatorics dp math two pointers Statement E Codeforces Global Round 22 {1738} PROGRAMMING 2500.0 Editorial of Codeforces Global Round <strong>22</strong>
10197 Card Game combinatorics constructive algorithms dp games Statement C Educational Codeforces Round 136 (Rated for Div. 2) {1739} PROGRAMMING Educational Codeforces Round 136 Editorial
1127 Conditional Mix combinatorics dp math Statement F Codeforces Round 831 (Div. 1 + Div. 2) {1740} PROGRAMMING 2500.0 Tutorial 2600
1844 Intersection and Union combinatorics data structures dp math matrices Statement F Educational Codeforces Round 137 (Rated for Div. 2) {1743} PROGRAMMING Educational Codeforces Round 137 Editorial 2300
352 Antifibonacci Cut bitmasks combinatorics dp math Statement G Educational Codeforces Round 137 (Rated for Div. 2) {1743} PROGRAMMING Educational Codeforces Round 137 Editorial 3000
29856 Password combinatorics implementation Statement A Educational Codeforces Round 137 (Rated for Div. 2) {1743} PROGRAMMING Educational Codeforces Round 137 Editorial 800
694 List Generation combinatorics math Statement E Codeforces Round 832 (Div. 2) {1747} PROGRAMMING 2500.0 Codeforces Round #832 (Div. 2) Editorial
3304 ConstructOR bitmasks chinese remainder theorem combinatorics constructive algorithms number theory Statement D Codeforces Round 833 (Div. 2) {1748} PROGRAMMING 2000.0 Codeforces Round #833 (Div. 2) Editorial 2100
7550 Count GCD bitmasks combinatorics dp math number theory Statement D CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!) {1750} PROGRAMMING 1750.0 CodeTON Round 3 (Div. 1 + Div. 2) Editorial