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2708 Grime Zoo constructive algorithms greedy implementation Statement D Technocup 2021 - Elimination Round 3 {1411} PROGRAMMING 2000.0 Technocup 2021 Elimination Round 3 and Round #692 (Div. 1 + Div. 2) Editorial
15278 Finding Sasuke constructive algorithms math Statement A Technocup 2021 - Elimination Round 1 {1413} PROGRAMMING 500.0 Codeforces Round 679 (Div. 1, Div. 2) and Technocup Round 1 editorial
2999 New Game Plus! constructive algorithms greedy math Statement E Technocup 2021 - Elimination Round 2 {1415} PROGRAMMING 2500.0 Editorial of Codeforces Round 687 (Technocup 2021 — Elimitation Round 2)
6668 Make Them Equal constructive algorithms greedy math Statement B Codeforces Round 673 (Div. 1) {1416} PROGRAMMING 1000.0 Codeforces Round #673 Editorial 2000
17367 Sage's Birthday (hard version) binary search constructive algorithms greedy implementation sortings two pointers Statement D2 Codeforces Round 671 (Div. 2) {1419} PROGRAMMING 1000.0 Codeforces Round #671 Editorial
3494 Decryption bitmasks constructive algorithms implementation math number theory Statement E Codeforces Round 671 (Div. 2) {1419} PROGRAMMING 2250.0 Codeforces Round #671 Editorial
16949 Stairs brute force constructive algorithms greedy implementation math two pointers Statement B Codeforces Round 671 (Div. 2) {1419} PROGRAMMING 750.0 Codeforces Round #671 Editorial
18944 Pokémon Army (easy version) constructive algorithms dp greedy Statement C1 Codeforces Round 672 (Div. 2) {1420} PROGRAMMING 1000.0 Editorial
13465 Putting Bricks in the Wall constructive algorithms implementation Statement B Codeforces Round 676 (Div. 2) {1421} PROGRAMMING 1000.0 Codeforces Round #676 (Div. 2) Editorial
13496 Palindromifier constructive algorithms strings Statement C Codeforces Round 676 (Div. 2) {1421} PROGRAMMING 1500.0 Codeforces Round #676 (Div. 2) Editorial
880 Bubble Cup hypothesis constructive algorithms dp math Statement J Bubble Cup 13 - Finals [Online Mirror, unrated, Div. 1] {1423} PROGRAMMING FinalsEditorial2020.pdf
20523 Increase and Copy binary search constructive algorithms math Statement C Codeforces Round 674 (Div. 3) {1426} PROGRAMMING 83120 1100
17571 Non-zero Segments constructive algorithms data structures greedy Statement D Codeforces Round 674 (Div. 3) {1426} PROGRAMMING 83120 1500
8116 Rock, Paper, Scissors brute force constructive algorithms flows greedy math Statement E Codeforces Round 674 (Div. 3) {1426} PROGRAMMING 83120 1800
3690 Unshuffling a Deck constructive algorithms implementation Statement D Codeforces Global Round 11 {1427} PROGRAMMING 1000.0 Editorial of Global Round 11 2000
1627 Xum bitmasks constructive algorithms math number theory Statement E Codeforces Global Round 11 {1427} PROGRAMMING 1500.0 Editorial of Global Round 11 2500
4720 Bouncing Boomerangs constructive algorithms greedy Statement D Codeforces Raif Round 1 (Div. 1 + Div. 2) {1428} PROGRAMMING 1500.0 Codeforces Raif Round 1 Editorial
28112 Numbers on Whiteboard constructive algorithms data structures games implementation math Statement C Educational Codeforces Round 96 (Rated for Div. 2) {1430} PROGRAMMING Educational Codeforces Round 96 — Editorial
30382 Districts Connection constructive algorithms dfs and similar trees Statement D Codeforces Round 677 (Div. 3) {1433} PROGRAMMING Codeforces Round #677 (Div. 3) Editorial
28568 Dominant Piranha constructive algorithms greedy Statement C Codeforces Round 677 (Div. 3) {1433} PROGRAMMING Codeforces Round #677 (Div. 3) Editorial
21710 Prime Square constructive algorithms math Statement B Codeforces Round 678 (Div. 2) {1436} PROGRAMMING 1000.0 Codeforces Round #678 (Div. 2). Editorial
18454 Marketing Scheme brute force constructive algorithms greedy math Statement A Educational Codeforces Round 97 (Rated for Div. 2) {1437} PROGRAMMING 84149
20809 Reverse Binary Strings constructive algorithms greedy Statement B Educational Codeforces Round 97 (Rated for Div. 2) {1437} PROGRAMMING 84149
28847 Valerii Against Everyone constructive algorithms greedy sortings Statement B Codeforces Round 682 (Div. 2) {1438} PROGRAMMING 750.0 Codeforces Round #682 (Div. 2) Editorial
5390 Binary Table (Hard Version) constructive algorithms graphs greedy implementation Statement A2 Codeforces Round 684 (Div. 1) {1439} PROGRAMMING 500.0 Codeforces Round #684[Div1 and Div2] Editorial
9796 Binary Table (Easy Version) constructive algorithms implementation Statement A1 Codeforces Round 684 (Div. 1) {1439} PROGRAMMING 500.0 Codeforces Round #684[Div1 and Div2] Editorial
16667 Kids Seating constructive algorithms math Statement A Codeforces Round 681 (Div. 2, based on VK Cup 2019-2020 - Final) {1443} PROGRAMMING 500.0 VK Cup 2019-2020 -- Engine Editorial
642 Rectangular Polyline constructive algorithms dp geometry Statement D Codeforces Round 680 (Div. 1, based on Moscow Team Olympiad) {1444} PROGRAMMING 2000.0 Codeforces Round #680 Editorial
122 Long Recovery constructive algorithms dfs and similar Statement E Codeforces Round 683 (Div. 1, by Meet IT) {1446} PROGRAMMING 3000.0 E
17642 Knapsack constructive algorithms greedy sortings Statement A Codeforces Round 683 (Div. 1, by Meet IT) {1446} PROGRAMMING 500.0 E
14442 Add Candies constructive algorithms math Statement A Codeforces Round 683 (Div. 2, by Meet IT) {1447} PROGRAMMING 500.0 Meet IT Codeforces Round Editorial
1419 Capitalism constructive algorithms dfs and similar graphs shortest paths Statement E Codeforces Global Round 12 {1450} PROGRAMMING 2500.0 Codeforces Global Round 12 Editorial
1463 The Struggling Contestant constructive algorithms greedy Statement F Codeforces Global Round 12 {1450} PROGRAMMING 2750.0 Codeforces Global Round 12 Editorial
4162 Errich-Tac-Toe (Hard Version) constructive algorithms math Statement C2 Codeforces Global Round 12 {1450} PROGRAMMING 750.0 Codeforces Global Round 12 Editorial
18475 Avoid Trygub constructive algorithms sortings Statement A Codeforces Global Round 12 {1450} PROGRAMMING 500.0 Codeforces Global Round 12 Editorial
4894 Bitwise Queries (Easy Version) bitmasks constructive algorithms interactive math Statement E1 Codeforces Round 685 (Div. 2) {1451} PROGRAMMING 1500.0 Editorial — Codeforces Round #685
3359 Bitwise Queries (Hard Version) bitmasks constructive algorithms interactive math Statement E2 Codeforces Round 685 (Div. 2) {1451} PROGRAMMING 1000.0 Editorial — Codeforces Round #685
366 Divide Powers constructive algorithms greedy Statement F Educational Codeforces Round 98 (Rated for Div. 2) {1452} PROGRAMMING 84847
4434 Checkpoints brute force constructive algorithms greedy math probabilities Statement D Codeforces Round 688 (Div. 2) {1453} PROGRAMMING 2000.0 Codeforces Round #688 (Div. 2) Editorial
14056 Suffix Operations constructive algorithms implementation Statement B Codeforces Round 688 (Div. 2) {1453} PROGRAMMING 1000.0 Codeforces Round #688 (Div. 2) Editorial
22076 Number into Sequence constructive algorithms math number theory Statement D Codeforces Round 686 (Div. 3) {1454} PROGRAMMING Codeforces Round #686 (Div. 3) Editorial
43952 Special Permutation constructive algorithms probabilities Statement A Codeforces Round 686 (Div. 3) {1454} PROGRAMMING Codeforces Round #686 (Div. 3) Editorial
1643 Four Points brute force constructive algorithms flows geometry greedy math ternary search Statement E Educational Codeforces Round 99 (Rated for Div. 2) {1455} PROGRAMMING 85186
20430 Ping-pong constructive algorithms games math Statement C Educational Codeforces Round 99 (Rated for Div. 2) {1455} PROGRAMMING 85186
23209 Jumps constructive algorithms math Statement B Educational Codeforces Round 99 (Rated for Div. 2) {1455} PROGRAMMING 85186
601 Mathematical Expression constructive algorithms dp greedy Statement F Codeforces Round 689 (Div. 2, based on Zed Code Competition) {1461} PROGRAMMING 2750.0 Codeforces Round #689 (Div. 2). Editorial
18994 String Generation constructive algorithms greedy Statement A Codeforces Round 689 (Div. 2, based on Zed Code Competition) {1461} PROGRAMMING 500.0 Codeforces Round #689 (Div. 2). Editorial
4826 Pairs binary search constructive algorithms greedy Statement D Educational Codeforces Round 100 (Rated for Div. 2) {1463} PROGRAMMING Educational Codeforces Round 100 Editorial
6780 Three Bags brute force constructive algorithms greedy Statement C Codeforces Round 695 (Div. 2) {1467} PROGRAMMING 1500.0 Codeforces Round #695 (Div. 2) Editorial 1900
1994 K and Medians constructive algorithms math Statement H 2020-2021 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules) {1468} PROGRAMMING Tutorial (PDF)
10189 Ceil Divisions brute force constructive algorithms math number theory Statement D Educational Codeforces Round 101 (Rated for Div. 2) {1469} PROGRAMMING Educational Codeforces Round 101 Editorial
29974 Regular Bracket Sequence constructive algorithms greedy Statement A Educational Codeforces Round 101 (Rated for Div. 2) {1469} PROGRAMMING Educational Codeforces Round 101 Editorial
1436 Strange Shuffle binary search brute force constructive algorithms interactive probabilities Statement C Codeforces Round 694 (Div. 1) {1470} PROGRAMMING 1000.0 86464
4177 Strange Housing constructive algorithms dfs and similar dsu graph matchings graphs Statement D Codeforces Round 694 (Div. 1) {1470} PROGRAMMING 1500.0 86464
40032 Different Divisors binary search constructive algorithms greedy math number theory Statement B Codeforces Round 696 (Div. 2) {1474} PROGRAMMING 1000.0 Codeforces Round #696 Editorial
14107 Array Destruction constructive algorithms data structures greedy implementation sortings Statement C Codeforces Round 696 (Div. 2) {1474} PROGRAMMING 1500.0 Codeforces Round #696 Editorial
1461 What Is It? constructive algorithms greedy Statement E Codeforces Round 696 (Div. 2) {1474} PROGRAMMING 2250.0 Codeforces Round #696 Editorial
5869 Unusual Matrix 2-sat constructive algorithms greedy Statement F Codeforces Round 697 (Div. 3) {1475} PROGRAMMING Codeforces Round #697 (Div. 3) Editorial
44736 K-divisible Sum binary search constructive algorithms greedy math Statement A Educational Codeforces Round 103 (Rated for Div. 2) {1476} PROGRAMMING 87356
12287 Longest Simple Cycle constructive algorithms dp graphs greedy Statement C Educational Codeforces Round 103 (Rated for Div. 2) {1476} PROGRAMMING 87356
6510 Nezzar and Board constructive algorithms math number theory Statement A Codeforces Round 698 (Div. 1) {1477} PROGRAMMING 500.0 87294 1800
2581 Nezzar and Nice Beatmap constructive algorithms geometry greedy sortings Statement C Codeforces Round 698 (Div. 1) {1477} PROGRAMMING 1500.0 87294 2200
781 Nezzar and Hidden Permutations constructive algorithms dfs and similar graphs Statement D Codeforces Round 698 (Div. 1) {1477} PROGRAMMING 2250.0 87294 2800
10616 Nezzar and Symmetric Array constructive algorithms implementation math sortings Statement C Codeforces Round 698 (Div. 2) {1478} PROGRAMMING 1500.0 Tutorial 1700
7462 Painting the Array I constructive algorithms data structures dp greedy implementation Statement B1 Codeforces Round 700 (Div. 1) {1479} PROGRAMMING 750.0 Editorial of Codeforces Round #700
12390 Fence Painting brute force constructive algorithms greedy implementation Statement C Codeforces Round 699 (Div. 2) {1481} PROGRAMMING 1500.0 Codeforces Round #699 (Div. 2) Editorial
4847 AB Graph constructive algorithms graphs greedy implementation strings Statement D Codeforces Round 699 (Div. 2) {1481} PROGRAMMING 2000.0 Codeforces Round #699 (Div. 2) Editorial
3852 Basic Diplomacy constructive algorithms flows greedy implementation Statement A Codeforces Round 709 (Div. 1, based on Technocup 2021 Final Round) {1483} PROGRAMMING 500.0 Technocup 2021: Final Round and Codeforces Round #709 — tutorial
5618 Multiples and Power Differences constructive algorithms math number theory Statement D Codeforces Round 701 (Div. 2) {1485} PROGRAMMING 1750.0 Editorial of Codeforces Round #701 (Div. 2) 2200
3345 Paired Payment binary search constructive algorithms dp graphs shortest paths Statement E Codeforces Round 703 (Div. 2) {1486} PROGRAMMING 2250.0 Codeforces Round #703 (Div. 2) Editorial
15386 Minimum Ties brute force constructive algorithms dfs and similar graphs greedy implementation math Statement C Educational Codeforces Round 104 (Rated for Div. 2) {1487} PROGRAMMING 87873
27864 Balanced Remainders brute force constructive algorithms math Statement B Codeforces Round 702 (Div. 3) {1490} PROGRAMMING Codeforces Round #702 (Div. 3) Editorial
1130 Magnets binary search constructive algorithms interactive Statement F Codeforces Global Round 13 {1491} PROGRAMMING 2000.0 Codeforces Global Round 13 Editorial
8257 Zookeeper and The Infinite Zoo bitmasks constructive algorithms math Statement D Codeforces Global Round 13 {1491} PROGRAMMING 1250.0 Codeforces Global Round 13 Editorial
1003 Switch and Flip constructive algorithms math Statement G Codeforces Global Round 13 {1491} PROGRAMMING 2250.0 Codeforces Global Round 13 Editorial
6507 Genius's Gambit bitmasks constructive algorithms math Statement D Codeforces Round 704 (Div. 2) {1492} PROGRAMMING 2250.0 Codeforces Round #704 Editorial
1288 Almost Fault-Tolerant Database brute force constructive algorithms dfs and similar greedy implementation Statement E Codeforces Round 704 (Div. 2) {1492} PROGRAMMING 3000.0 Codeforces Round #704 Editorial
19769 Anti-knapsack constructive algorithms greedy Statement A Codeforces Round 705 (Div. 2) {1493} PROGRAMMING 750.0 Codeforces Round #705 (Div.2) Editorial
2814 Dogeforces brute force constructive algorithms divide and conquer dsu greedy implementation trees Statement D Educational Codeforces Round 105 (Rated for Div. 2) {1494} PROGRAMMING Educational Codeforces Round 105 Editorial
2052 A-Z Graph constructive algorithms data structures graphs Statement E Educational Codeforces Round 105 (Rated for Div. 2) {1494} PROGRAMMING Educational Codeforces Round 105 Editorial
420 Squares constructive algorithms data structures graphs trees Statement F Codeforces Round 706 (Div. 1) {1495} PROGRAMMING 3250.0 Codeforces Round #706 Editorial
6327 Let's Go Hiking constructive algorithms games greedy implementation Statement B Codeforces Round 706 (Div. 1) {1495} PROGRAMMING 1000.0 Codeforces Round #706 Editorial
2904 Garden of the Sun constructive algorithms graphs Statement C Codeforces Round 706 (Div. 1) {1495} PROGRAMMING 1500.0 Codeforces Round #706 Editorial
22231 Split it! brute force constructive algorithms greedy strings Statement A Codeforces Round 706 (Div. 2) {1496} PROGRAMMING 500.0 Codeforces Round #706 Editorial
27176 M-arrays constructive algorithms greedy math Statement B Codeforces Round 708 (Div. 2) {1497} PROGRAMMING 750.0 Codeforces Round #708 Editorial 1200
29156 k-LCM (easy version) constructive algorithms math Statement C1 Codeforces Round 708 (Div. 2) {1497} PROGRAMMING 750.0 Codeforces Round #708 Editorial 1200
19431 k-LCM (hard version) constructive algorithms math Statement C2 Codeforces Round 708 (Div. 2) {1497} PROGRAMMING 500.0 Codeforces Round #708 Editorial 1600
21960 Domino on Windowsill constructive algorithms math Statement A Educational Codeforces Round 106 (Rated for Div. 2) {1499} PROGRAMMING Educational Codeforces Round 106 Editorial
910 Matrix Sorting bitmasks constructive algorithms dfs and similar greedy hashing string suffix structures two pointers Statement C Codeforces Round 707 (Div. 1, based on Moscow Open Olympiad in Informatics) {1500} PROGRAMMING 1500.0 Codeforces Round #707 Editorial 2600
14573 Balance the Bits constructive algorithms greedy Statement A Codeforces Round 712 (Div. 1) {1503} PROGRAMMING 750.0 T 1600
7667 3-Coloring constructive algorithms games interactive Statement B Codeforces Round 712 (Div. 1) {1503} PROGRAMMING 1000.0 T 1700
1255 Flip the Cards 2-sat constructive algorithms data structures dsu greedy sortings Statement D Codeforces Round 712 (Div. 1) {1503} PROGRAMMING 1750.0 T 2600
215 Balance the Cards constructive algorithms data structures divide and conquer geometry graphs implementation Statement F Codeforces Round 712 (Div. 1) {1503} PROGRAMMING 4000.0 T 3500
25540 Flip the Bits constructive algorithms greedy implementation math Statement B Codeforces Round 712 (Div. 2) {1504} PROGRAMMING 1000.0 Codeforces Round #712 Editorial 1200
22778 Déjà Vu constructive algorithms strings Statement A Codeforces Round 712 (Div. 2) {1504} PROGRAMMING 500.0 Codeforces Round #712 Editorial 800
1921 Cakewalk constructive algorithms greedy implementation shortest paths Statement E April Fools Day Contest 2021 {1505} PROGRAMMING tutorial
6514 DMCA constructive algorithms implementation Statement B April Fools Day Contest 2021 {1505} PROGRAMMING tutorial
6701 Fibonacci Words constructive algorithms implementation Statement C April Fools Day Contest 2021 {1505} PROGRAMMING tutorial
14176 Restoring the Permutation constructive algorithms data structures dsu greedy Statement E Codeforces Round 710 (Div. 3) {1506} PROGRAMMING Editorial
25380 Epic Transformation constructive algorithms greedy Statement D Codeforces Round 710 (Div. 3) {1506} PROGRAMMING Editorial
3692 Triangular Paths constructive algorithms greedy math shortest paths sortings Statement F Codeforces Round 710 (Div. 3) {1506} PROGRAMMING Editorial
4414 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
391 Tree Calendar brute force constructive algorithms dfs and similar sortings Statement E Codeforces Round 715 (Div. 1) {1508} PROGRAMMING 2250.0 Codeforces Round #715 Editorial
711 Swap Pass constructive algorithms geometry sortings Statement D Codeforces Round 715 (Div. 1) {1508} PROGRAMMING 2250.0 Codeforces Round #715 Editorial
6662 Binary Literature constructive algorithms greedy implementation math strings two pointers Statement A Codeforces Round 715 (Div. 1) {1508} PROGRAMMING 750.0 Codeforces Round #715 Editorial
561 Japanese Game constructive algorithms math Statement J 2020-2021 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1510} PROGRAMMING nerc-2020-offline-tutorial.pdf
12429 Min Cost String brute force constructive algorithms dfs and similar graphs greedy Statement D Educational Codeforces Round 107 (Rated for Div. 2) {1511} PROGRAMMING 89634
24637 GCD Length constructive algorithms math number theory Statement B Educational Codeforces Round 107 (Rated for Div. 2) {1511} PROGRAMMING 89634
24493 Corrupted Array constructive algorithms data structures greedy Statement D Codeforces Round 713 (Div. 3) {1512} PROGRAMMING Codeforces Round #713 (Div. 3) Editorial
21676 A-B Palindrome constructive algorithms implementation strings Statement C Codeforces Round 713 (Div. 3) {1512} PROGRAMMING Codeforces Round #713 (Div. 3) Editorial
1427 Swapping Problem brute force constructive algorithms data structures sortings Statement F Divide by Zero 2021 and Codeforces Round 714 (Div. 2) {1513} PROGRAMMING 3500.0 Divide by Zero 2021 and Codeforces Round #714 (Div. 2) Editorial
1675 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
6451 GCD and MST constructive algorithms data structures dsu graphs implementation number theory sortings Statement D Divide by Zero 2021 and Codeforces Round 714 (Div. 2) {1513} PROGRAMMING 2000.0 Divide by Zero 2021 and Codeforces Round #714 (Div. 2) Editorial
20008 Array and Peaks constructive algorithms implementation Statement A Divide by Zero 2021 and Codeforces Round 714 (Div. 2) {1513} PROGRAMMING 500.0 Divide by Zero 2021 and Codeforces Round #714 (Div. 2) Editorial
18111 Product 1 Modulo N constructive algorithms math number theory Statement C Codeforces Round 716 (Div. 2) {1514} PROGRAMMING 1500.0 Codeforces round #716 editorial
18717 Phoenix and Towers constructive algorithms data structures greedy Statement C Codeforces Global Round 14 {1515} PROGRAMMING 1500.0 Editorial
2068 Phoenix and Earthquake constructive algorithms dfs and similar dsu graphs greedy trees Statement F Codeforces Global Round 14 {1515} PROGRAMMING 3250.0 Editorial
21099 Phoenix and Gold constructive algorithms math Statement A Codeforces Global Round 14 {1515} PROGRAMMING 500.0 Editorial
14052 Baby Ehab Partitions Again bitmasks constructive algorithms dp math Statement C Codeforces Round 717 (Div. 2) {1516} PROGRAMMING 1500.0 Codeforces round #717 editorial
14160 Fillomino 2 constructive algorithms greedy implementation Statement C Contest 2050 and Codeforces Round 718 (Div. 1 + Div. 2) {1517} PROGRAMMING 1500.0 Contest 2050 and Codeforces Round #718 (Div.1 + Div.2) Editorial
13821 Morning Jogging constructive algorithms greedy sortings Statement B Contest 2050 and Codeforces Round 718 (Div. 1 + Div. 2) {1517} PROGRAMMING 1250.0 Contest 2050 and Codeforces Round #718 (Div.1 + Div.2) Editorial
893 Off by One constructive algorithms dfs and similar geometry graphs sortings trees Statement E Educational Codeforces Round 108 (Rated for Div. 2) {1519} PROGRAMMING Educational Codeforces Round 108 Editorial
729 Nastia and a Beautiful Matrix binary search constructive algorithms greedy math Statement E Codeforces Round 720 (Div. 2) {1521} PROGRAMMING 2750.0 90477
2289 Nastia Plays with a Tree constructive algorithms data structures dfs and similar dp flows graphs greedy implementation trees Statement D Codeforces Round 720 (Div. 2) {1521} PROGRAMMING 2250.0 90477
4603 Nastia and a Hidden Permutation constructive algorithms interactive Statement C Codeforces Round 720 (Div. 2) {1521} PROGRAMMING 1750.0 90477
41960 Nastia and Nearly Good Numbers constructive algorithms math Statement A Codeforces Round 720 (Div. 2) {1521} PROGRAMMING 500.0 90477
22897 Nastia and a Good Array constructive algorithms math Statement B Codeforces Round 720 (Div. 2) {1521} PROGRAMMING 1000.0 90477
26592 Permutation Sort constructive algorithms greedy Statement B Educational Codeforces Round 109 (Rated for Div. 2) {1525} PROGRAMMING 90793
2791 Kill Anton brute force constructive algorithms data structures math strings Statement D Codeforces Round 723 (Div. 2) {1526} PROGRAMMING 2250.0 Codeforces Round #723 (Div. 2) Editorial
1413 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
388 Median Queries constructive algorithms interactive probabilities Statement F Codeforces Round 723 (Div. 2) {1526} PROGRAMMING 3500.0 Codeforces Round #723 (Div. 2) Editorial
24994 Mean Inequality constructive algorithms sortings Statement A Codeforces Round 723 (Div. 2) {1526} PROGRAMMING 500.0 Codeforces Round #723 (Div. 2) Editorial
2283 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
31003 Eshag Loves Big Arrays constructive algorithms greedy Statement A Codeforces Round 722 (Div. 2) {1529} PROGRAMMING 500.0 Codeforces Round #722 Editorial
10073 Secret Santa constructive algorithms flows graphs math probabilities Statement D Codeforces Round 733 (Div. 1 + Div. 2, based on VK Cup 2021 - Elimination (Engine)) {1530} PROGRAMMING 1500.0 Codeforces Round #733 Editorial (all problems)
3250 Minimax constructive algorithms greedy implementation strings Statement E Codeforces Round 733 (Div. 1 + Div. 2, based on VK Cup 2021 - Elimination (Engine)) {1530} PROGRAMMING 2000.0 Codeforces Round #733 Editorial (all problems)
16274 Putting Plates constructive algorithms implementation Statement B Codeforces Round 733 (Div. 1 + Div. 2, based on VK Cup 2021 - Elimination (Engine)) {1530} PROGRAMMING 750.0 Codeforces Round #733 Editorial (all problems)
61 Excursions *special constructive algorithms dfs and similar flows graphs Statement I Kotlin Heroes: Episode 7 {1533} PROGRAMMING Kotlin Heroes 7 — Editorial
98 Biome Map *special constructive algorithms dfs and similar graphs Statement G Kotlin Heroes: Episode 7 {1533} PROGRAMMING Kotlin Heroes 7 — Editorial
838 A New Beginning constructive algorithms dp Statement G Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) {1534} PROGRAMMING 3250.0 Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) Editorial
2073 Lost Array constructive algorithms dp graphs interactive shortest paths Statement E Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) {1534} PROGRAMMING 2250.0 Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) Editorial
6785 Lost Tree constructive algorithms interactive trees Statement D Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) {1534} PROGRAMMING 1500.0 Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) Editorial
2803 Figure Fixing constructive algorithms dfs and similar dsu graphs math Statement F Codeforces Round 726 (Div. 2) {1537} PROGRAMMING 2000.0 Codeforces Round #726 (Div.2) Editorial
42034 Bad Boy constructive algorithms greedy math Statement B Codeforces Round 726 (Div. 2) {1537} PROGRAMMING 750.0 Codeforces Round #726 (Div.2) Editorial
15224 Another Problem About Dividing Numbers constructive algorithms number theory Statement D Codeforces Round 725 (Div. 3) {1538} PROGRAMMING Codeforces Round #725 (Div. 3) Editorial
1053 Game with Cards binary search constructive algorithms data structures dp implementation Statement E Codeforces Round 727 (Div. 2) {1539} PROGRAMMING 2000.0 tutorial 2500
14957 Great Graphs constructive algorithms graphs greedy shortest paths sortings Statement A Codeforces Round 728 (Div. 1) {1540} PROGRAMMING 500.0 Tutorial
30692 Pretty Permutations constructive algorithms greedy implementation Statement A Codeforces Round 728 (Div. 2) {1541} PROGRAMMING 500.0 Tutorial
26462 Plus and Multiply constructive algorithms math number theory Statement B Codeforces Round 729 (Div. 2) {1542} PROGRAMMING 1250.0
7995 RPD and Rap Sheet (Easy Version) bitmasks constructive algorithms interactive math Statement D1 Codeforces Round 730 (Div. 2) {1543} PROGRAMMING 1000.0 Codeforces Round #730 (Div. 2) Editorial
2162 RPD and Rap Sheet (Hard Version) constructive algorithms dp interactive math Statement D2 Codeforces Round 730 (Div. 2) {1543} PROGRAMMING 1250.0 Codeforces Round #730 (Div. 2) Editorial
442 The Final Pursuit constructive algorithms graphs greedy Statement E Codeforces Round 730 (Div. 2) {1543} PROGRAMMING 3000.0 Codeforces Round #730 (Div. 2) Editorial
765 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
605 AquaMoon and Wrong Coordinate constructive algorithms interactive math Statement D Codeforces Round 732 (Div. 1) {1545} PROGRAMMING 2250.0 Codeforces Round #732 Editorial 3000
6913 Array Stabilization (GCD version) binary search constructive algorithms data structures number theory two pointers Statement F Codeforces Round 731 (Div. 3) {1547} PROGRAMMING Codeforces Round #731 (Div. 3) Editorial
2055 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
16636 Wonderful Coloring - 2 binary search constructive algorithms data structures greedy Statement B2 Codeforces Round 734 (Div. 3) {1551} PROGRAMMING Editorial for Codeforces Round #734 (Div.3)
2983 Domino (hard version) constructive algorithms implementation math Statement D2 Codeforces Round 734 (Div. 3) {1551} PROGRAMMING Editorial for Codeforces Round #734 (Div.3)
7556 Domino (easy version) constructive algorithms math Statement D1 Codeforces Round 734 (Div. 3) {1551} PROGRAMMING Editorial for Codeforces Round #734 (Div.3)
6279 Maximize the Intersections combinatorics constructive algorithms geometry greedy Statement C Codeforces Global Round 15 {1552} PROGRAMMING 1000.0 Editorial of Global Round 15
2122 Colors and Intervals constructive algorithms data structures greedy sortings Statement E Codeforces Global Round 15 {1552} PROGRAMMING 1500.0 Editorial of Global Round 15
3767 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
10544 Diane constructive algorithms greedy strings Statement D Codeforces Round 735 (Div. 2) {1554} PROGRAMMING 2000.0 Editorial of Codeforces Round #735 (Div. 2) 1800
24024 Coin Rows brute force constructive algorithms dp implementation Statement C Educational Codeforces Round 112 (Rated for Div. 2) {1555} PROGRAMMING 93389 1300
8548 Take a Guess bitmasks constructive algorithms interactive math Statement D Deltix Round, Summer 2021 (open for everyone, rated, Div. 1 + Div. 2) {1556} PROGRAMMING 1500.0 94384 1800
3708 Bottom-Tier Reversals constructive algorithms greedy Statement C Codeforces Round 740 (Div. 1, based on VK Cup 2021 - Final (Engine)) {1558} PROGRAMMING 1500.0 Codeforces Round #740 Editorial 2000
22739 Mocha and Hiking constructive algorithms graphs Statement C Codeforces Round 738 (Div. 2) {1559} PROGRAMMING 1000.0 Tutorial (en) 1200
15973 Mocha and Diana (Easy Version) brute force constructive algorithms dsu graphs greedy trees Statement D1 Codeforces Round 738 (Div. 2) {1559} PROGRAMMING 1500.0 Tutorial (en) 1400
3048 Mocha and Diana (Hard Version) brute force constructive algorithms dfs and similar dsu graphs greedy trees two pointers Statement D2 Codeforces Round 738 (Div. 2) {1559} PROGRAMMING 1500.0 Tutorial (en) 2500
45216 Mocha and Math bitmasks constructive algorithms math Statement A Codeforces Round 738 (Div. 2) {1559} PROGRAMMING 500.0 Tutorial (en) 900
6741 Nearest Beautiful Number (easy version) binary search bitmasks brute force constructive algorithms dfs and similar greedy Statement F1 Codeforces Round 739 (Div. 3) {1560} PROGRAMMING 94009 1900
4928 Nearest Beautiful Number (hard version) bitmasks brute force constructive algorithms dfs and similar dp greedy Statement F2 Codeforces Round 739 (Div. 3) {1560} PROGRAMMING 94009 2100
2240 Two Hundred Twenty One (hard version) binary search constructive algorithms data structures dp math Statement D2 Codeforces Round 741 (Div. 2) {1562} PROGRAMMING 1250.0 Editorial of Codeforces Round 741 (Div. 2)
6641 Two Hundred Twenty One (easy version) constructive algorithms dp math Statement D1 Codeforces Round 741 (Div. 2) {1562} PROGRAMMING 1250.0 Editorial of Codeforces Round 741 (Div. 2)
14298 Rings constructive algorithms math Statement C Codeforces Round 741 (Div. 2) {1562} PROGRAMMING 1250.0 Editorial of Codeforces Round 741 (Div. 2)
21177 MIN-MEX Cut bitmasks constructive algorithms dp Statement B Codeforces Global Round 16 {1566} PROGRAMMING 750.0 Codeforces Global Round 16 Editorial
18999 MAX-MEX Cut bitmasks constructive algorithms dp greedy Statement C Codeforces Global Round 16 {1566} PROGRAMMING 1000.0 Codeforces Global Round 16 Editorial
383 Four Vertices constructive algorithms data structures graphs greedy implementation shortest paths Statement G Codeforces Global Round 16 {1566} PROGRAMMING 3000.0 Codeforces Global Round 16 Editorial
152 Xor-quiz constructive algorithms dp interactive math number theory Statement H Codeforces Global Round 16 {1566} PROGRAMMING 3750.0 Codeforces Global Round 16 Editorial
877 One-Four Overload 2-sat constructive algorithms dfs and similar geometry graphs implementation Statement F Codeforces Round 742 (Div. 2) {1567} PROGRAMMING 2750.0 Codeforces Round #742 Editorial
4842 Expression Evaluation Error constructive algorithms greedy implementation math Statement D Codeforces Round 742 (Div. 2) {1567} PROGRAMMING 1750.0 Codeforces Round #742 Editorial
368 Sweepstake *special brute force constructive algorithms implementation math Statement D Kotlin Heroes: Episode 8 {1571} PROGRAMMING Kotlin Heroes 8 Editorial
225 Kotlinforces *special constructive algorithms dp Statement F Kotlin Heroes: Episode 8 {1571} PROGRAMMING Kotlin Heroes 8 Editorial
2004 Xor of 3 brute force constructive algorithms greedy Statement B Codeforces Round 743 (Div. 1) {1572} PROGRAMMING 1250.0 Tutorial 2500
1037 Coloring combinatorics constructive algorithms implementation Statement E Educational Codeforces Round 114 (Rated for Div. 2) {1574} PROGRAMMING 95188
419 Anti-Tetris constructive algorithms graphs shortest paths Statement A ICPC WF Moscow Invitational Contest - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1578} PROGRAMMING Tutorial (PDF)
508 The Mind constructive algorithms interactive probabilities Statement M ICPC WF Moscow Invitational Contest - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1578} PROGRAMMING Tutorial (PDF)
25071 Permutation Minimization by Deque constructive algorithms greedy math Statement E1 Codeforces Round 744 (Div. 3) {1579} PROGRAMMING Codeforces Round #744 (Div. 3) Editorial
123 Railway Construction brute force constructive algorithms data structures graphs shortest paths Statement E Codeforces Round 745 (Div. 1) {1580} PROGRAMMING 3500.0 Codeforces Round #745 Editorial 3400
12450 Diameter of Graph constructive algorithms graphs greedy math Statement B Codeforces Round 745 (Div. 2) {1581} PROGRAMMING 1000.0 Codeforces Round #745 Editorial 1200
11569 Vupsen, Pupsen and 0 constructive algorithms math Statement D Codeforces Round 750 (Div. 2) {1582} PROGRAMMING 1750.0 Codeforces Round #750 (Div.2) Editorial
1528 Defender of Childhood Dreams bitmasks constructive algorithms divide and conquer Statement F Technocup 2022 - Elimination Round 1 {1583} PROGRAMMING 2750.0 Editorial for Technocup 2022 — Elimination Round 1 and Codeforces Round #749 (Div. 1+Div. 2)
2479 Moment of Bloom constructive algorithms dfs and similar graph matchings graphs greedy Statement E Technocup 2022 - Elimination Round 1 {1583} PROGRAMMING 2250.0 Editorial for Technocup 2022 — Elimination Round 1 and Codeforces Round #749 (Div. 1+Div. 2)
5928 Omkar and the Meaning of Life constructive algorithms interactive Statement D Technocup 2022 - Elimination Round 1 {1583} PROGRAMMING 1750.0 Editorial for Technocup 2022 — Elimination Round 1 and Codeforces Round #749 (Div. 1+Div. 2)
13231 Omkar and Heavenly Tree constructive algorithms trees Statement B Technocup 2022 - Elimination Round 1 {1583} PROGRAMMING 1000.0 Editorial for Technocup 2022 — Elimination Round 1 and Codeforces Round #749 (Div. 1+Div. 2)
298 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)
9105 Bakry and Partitioning bitmasks constructive algorithms dfs and similar dp graphs trees Statement C Codeforces Round 746 (Div. 2) {1592} PROGRAMMING 1500.0 95583
9321 The Number of Imposters constructive algorithms dfs and similar dp dsu graphs Statement D Codeforces Round 747 (Div. 2) {1594} PROGRAMMING 1750.0 95525 1700
1533 Ideal Farm constructive algorithms math Statement F Codeforces Round 747 (Div. 2) {1594} PROGRAMMING 2750.0 95525 2400
858 Weights constructive algorithms greedy two pointers Statement A Bubble Cup 14 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred, Div. 1) {1599} PROGRAMMING Tutorial
14734 Divine Array constructive algorithms implementation Statement B Codeforces Round 751 (Div. 2) {1602} PROGRAMMING 1000.0 95865 1100
17808 Di-visible Confusion constructive algorithms math number theory Statement A Codeforces Round 752 (Div. 1) {1603} PROGRAMMING 750.0 Editorial of Codeforces Round #752 1300
14997 Moderate Modular Mode constructive algorithms math number theory Statement B Codeforces Round 752 (Div. 1) {1603} PROGRAMMING 1000.0 Editorial of Codeforces Round #752 1600
3243 Treelabeling bitmasks constructive algorithms dfs and similar games graphs greedy trees Statement D Codeforces Round 754 (Div. 2) {1605} PROGRAMMING 2000.0 tutorial 2100
1574 Red-Blue Matrix constructive algorithms data structures hashing implementation sortings two pointers Statement D Educational Codeforces Round 116 (Rated for Div. 2) {1606} PROGRAMMING 96454
15189 Banknotes constructive algorithms greedy Statement C Educational Codeforces Round 116 (Rated for Div. 2) {1606} PROGRAMMING 96454
37181 AB Balance constructive algorithms strings Statement A Educational Codeforces Round 116 (Rated for Div. 2) {1606} PROGRAMMING 96454
12470 Build the Permutation constructive algorithms greedy Statement B Codeforces Round 758 (Div.1 + Div. 2) {1608} PROGRAMMING 750.0 Editorial of Codeforces Round #758 (Div.1 + Div. 2)
20236 Find Array constructive algorithms math Statement A Codeforces Round 758 (Div.1 + Div. 2) {1608} PROGRAMMING 250.0 Editorial of Codeforces Round #758 (Div.1 + Div. 2)
702 Mashtali: a Space Oddysey constructive algorithms dfs and similar graphs implementation Statement F Codeforces Global Round 17 {1610} PROGRAMMING 2750.0 Codeforces Global Round 17 Editorial
17061 Anti Light's Cell Guessing constructive algorithms implementation math Statement A Codeforces Global Round 17 {1610} PROGRAMMING 500.0 Codeforces Global Round 17 Editorial
11574 Weights Assignment For Tree Edges constructive algorithms trees Statement D Codeforces Round 756 (Div. 3) {1611} PROGRAMMING Tutorial 1500
31856 Team Composition: Programmers and Mathematicians binary search constructive algorithms math Statement B Codeforces Round 756 (Div. 3) {1611} PROGRAMMING Tutorial 800
33378 Make Even constructive algorithms math Statement A Codeforces Round 756 (Div. 3) {1611} PROGRAMMING Tutorial 800
997 Max Sum Array combinatorics constructive algorithms greedy sortings Statement G Educational Codeforces Round 117 (Rated for Div. 2) {1612} PROGRAMMING 97164
5879 Crazy Robot constructive algorithms dfs and similar graphs Statement E Educational Codeforces Round 118 (Rated for Div. 2) {1613} PROGRAMMING 97467
28800 Divan and a New Project constructive algorithms sortings Statement B Codeforces Round 757 (Div. 2) {1614} PROGRAMMING 750.0 Tutorial 1000
11282 Divan and bitwise operations bitmasks combinatorics constructive algorithms dp math Statement C Codeforces Round 757 (Div. 2) {1614} PROGRAMMING 1500.0 Tutorial 1500
24567 Divan and a Store brute force constructive algorithms greedy Statement A Codeforces Round 757 (Div. 2) {1614} PROGRAMMING 500.0 Tutorial 800
384 Reindeer Games constructive algorithms flows graphs shortest paths Statement H Codeforces Global Round 18 {1615} PROGRAMMING 4000.0 Global Round 18 Editorial
172 Maximum Adjacent Pairs constructive algorithms graph matchings Statement G Codeforces Global Round 18 {1615} PROGRAMMING 3750.0 Global Round 18 Editorial
26657 GCD Problem brute force constructive algorithms math Statement B Codeforces Round 761 (Div. 2) {1617} PROGRAMMING 1000.0 Editorial for Codeforces Round #761 (Div. 2)
5155 Too Many Impostors (easy version) constructive algorithms interactive Statement D1 Codeforces Round 761 (Div. 2) {1617} PROGRAMMING 2000.0 Editorial for Codeforces Round #761 (Div. 2)
2018 Too Many Impostors (hard version) constructive algorithms interactive Statement D2 Codeforces Round 761 (Div. 2) {1617} PROGRAMMING 1000.0 Editorial for Codeforces Round #761 (Div. 2)
16993 Forbidden Subsequence constructive algorithms sortings strings Statement A Codeforces Round 761 (Div. 2) {1617} PROGRAMMING 750.0 Editorial for Codeforces Round #761 (Div. 2)
7779 Singers' Tour constructive algorithms math Statement E Codeforces Round 760 (Div. 3) {1618} PROGRAMMING Codeforces Round #760 (Div. 3) Editorial
10188 MEX and Increments constructive algorithms data structures dp greedy math sortings Statement E Codeforces Round 762 (Div. 3) {1619} PROGRAMMING Tutorial
2334 Let's Play the Hat? constructive algorithms math Statement F Codeforces Round 762 (Div. 3) {1619} PROGRAMMING Tutorial
4795 Exact Change binary search brute force constructive algorithms greedy Statement D Educational Codeforces Round 119 (Rated for Div. 2) {1620} PROGRAMMING 98061
23075 Equal or Not Equal constructive algorithms implementation Statement A Educational Codeforces Round 119 (Rated for Div. 2) {1620} PROGRAMMING 98061
4389 The Winter Hike constructive algorithms greedy math Statement D Hello 2022 {1621} PROGRAMMING 1750.0
855 Quadratic Set constructive algorithms hashing number theory Statement F Educational Codeforces Round 120 (Rated for Div. 2) {1622} PROGRAMMING Educational Codeforces Round 120 Editorial
3777 Interacdive Problem binary search constructive algorithms interactive Statement F Codeforces Round 764 (Div. 3) {1624} PROGRAMMING Codeforces Round #764 (Div. 3) Editorial
4585 Masha-forgetful brute force constructive algorithms dp hashing implementation strings Statement E Codeforces Round 764 (Div. 3) {1624} PROGRAMMING Codeforces Round #764 (Div. 3) Editorial
26796 Division by Two and Permutation constructive algorithms flows graph matchings greedy math Statement C Codeforces Round 764 (Div. 3) {1624} PROGRAMMING Codeforces Round #764 (Div. 3) Editorial
16207 Not Assigning constructive algorithms dfs and similar number theory trees Statement C Codeforces Round 766 (Div. 2) {1627} PROGRAMMING 1250.0 Codeforces Round #766 (Div. 2) Editorial
24887 Not Shading constructive algorithms implementation Statement A Codeforces Round 766 (Div. 2) {1627} PROGRAMMING 500.0 Codeforces Round #766 (Div. 2) Editorial
16954 Meximum Array brute force constructive algorithms greedy math Statement A Codeforces Round 767 (Div. 1) {1628} PROGRAMMING 500.0 99276
3569 Grid Xor constructive algorithms greedy implementation interactive math Statement C Codeforces Round 767 (Div. 1) {1628} PROGRAMMING 1250.0 99276
2087 Fair Share constructive algorithms data structures dfs and similar graph matchings graphs Statement E Codeforces Round 770 (Div. 2) {1634} PROGRAMMING 2500.0 Codeforces Round #770 (Div. 2) editorial
4714 Finding Zero constructive algorithms greedy interactive Statement D Codeforces Round 770 (Div. 2) {1634} PROGRAMMING 2000.0 Codeforces Round #770 (Div. 2) editorial
19075 OKEA constructive algorithms math Statement C Codeforces Round 770 (Div. 2) {1634} PROGRAMMING 1500.0 Codeforces Round #770 (Div. 2) editorial
2720 Cars constructive algorithms dfs and similar dsu graphs greedy sortings Statement E Codeforces Round 772 (Div. 2) {1635} PROGRAMMING 2250.0 Codeforces Round #772 Editorial
24955 Differential Sorting constructive algorithms greedy Statement C Codeforces Round 772 (Div. 2) {1635} PROGRAMMING 1500.0 Codeforces Round #772 Editorial
2158 Towers constructive algorithms dfs and similar dp greedy trees Statement F Codeforces Global Round 19 {1637} PROGRAMMING 3250.0 Tutorial
18717 Andrew and Stones constructive algorithms greedy Statement C Codeforces Global Round 19 {1637} PROGRAMMING 1500.0 Tutorial
620 Birthday constructive algorithms math Statement G Codeforces Global Round 19 {1637} PROGRAMMING 4000.0 Tutorial
4060 Repetitions Decoding constructive algorithms implementation sortings Statement B Codeforces Round 773 (Div. 1) {1641} PROGRAMMING 1250.0 Codeforces Round #773 editorial
21280 Anti-Fibonacci Permutation brute force constructive algorithms implementation Statement B Educational Codeforces Round 123 (Rated for Div. 2) {1644} PROGRAMMING 100227
19380 Factorials and Powers of Two bitmasks brute force constructive algorithms math Statement C Codeforces Round 774 (Div. 2) {1646} PROGRAMMING 1250.0 Codeforces Round #774 (Div. 2) Editorial 1500