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3755 Petya and His Friends constructive algorithms math number theory Statement D Codeforces Beta Round 61 (Div. 2) {66} PROGRAMMING Codeforces Beta Round #61 (Div. 2): Editorial 1700
465 Tetris revisited constructive algorithms graph matchings greedy math Statement B Yandex.Algorithm 2011: Round 2 {86} PROGRAMMING Problemset analysis (Yandex, Round 2) 2100
30711 Hexadecimal's theorem brute force constructive algorithms implementation number theory Statement A Codeforces Round 125 (Div. 2) {199} PROGRAMMING Solutions for Codeforces Round #125 1000
10300 Buggy Sorting constructive algorithms greedy sortings Statement A Codeforces Round 151 (Div. 2) {246} PROGRAMMING Codeforces Round #151 (Div. 2) Tutorial 1000
661 Three Horses constructive algorithms math number theory Statement E Codeforces Round 166 (Div. 2) {271} PROGRAMMING 6662 2500
8838 Levko and Permutation constructive algorithms math number theory Statement B Codeforces Round 210 (Div. 2) {361} PROGRAMMING Codeforces Round #210 editorial 1200
10604 Mashmokh and Numbers constructive algorithms number theory Statement A Codeforces Round 240 (Div. 1) {414} PROGRAMMING Codeforces Round #240 Editorial 1500
4188 Devu and Partitioning of the Array brute force constructive algorithms implementation number theory Statement C Codeforces Round 251 (Div. 2) {439} PROGRAMMING Codeforces Round #251 Editorial 1700
2604 Jzzhu and Apples constructive algorithms number theory Statement C Codeforces Round 257 (Div. 1) {449} PROGRAMMING Codeforces Round #257 Editorial 2500
1055 Little Victor and Set brute force constructive algorithms math Statement D Codeforces Round 262 (Div. 2) {460} PROGRAMMING 13465 2500
3103 Prefix Product Sequence constructive algorithms math number theory Statement C Codeforces Round 278 (Div. 1) {487} PROGRAMMING Tutorial 2600
14028 Soldier and Number Game constructive algorithms dp math number theory Statement D Codeforces Round 304 (Div. 2) {546} PROGRAMMING Codeforces Round #304 (Div.2) editorial 1700
8395 GCD Table constructive algorithms greedy number theory Statement A Codeforces Round 323 (Div. 1) {582} PROGRAMMING Codeforces Round #323 Editorial 1700
7301 A Trivial Problem brute force constructive algorithms math number theory Statement B Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 1300
4216 Simple Subset constructive algorithms greedy number theory Statement D Educational Codeforces Round 12 {665} PROGRAMMING Editorial 2000
24225 Alyona and Numbers constructive algorithms math number theory Statement A Codeforces Round 358 (Div. 2) {682} PROGRAMMING 45491 1200
13552 Vladik and fractions brute force constructive algorithms math number theory Statement C Codeforces Round 384 (Div. 2) {743} PROGRAMMING Codeforces Round #384 Editorial 1500
38827 Mahmoud and a Triangle constructive algorithms geometry greedy math number theory sortings Statement B Codeforces Round 396 (Div. 2) {766} PROGRAMMING Codeforces round #396 editorial 1100
1480 Vulnerable Kerbals constructive algorithms dp graphs math number theory Statement C VK Cup 2017 - Round 2 {772} PROGRAMMING VK Cup Round 2 + Codeforces Round #409 Tutorial 2400
26450 Sherlock and his girlfriend constructive algorithms number theory Statement B ICM Technex 2017 and Codeforces Round 400 (Div. 1 + Div. 2, combined) {776} PROGRAMMING ICM Technex 2017 and Codeforces Round #400 (Div. 1 + Div. 2, combined) Editorial 1200
397 Madness constructive algorithms dfs and similar trees Statement F Codeforces Round 422 (Div. 2) {822} PROGRAMMING Codeforces Round #422 (Div. 2) Editorial 2700
4718 Ralph And His Magic Field combinatorics constructive algorithms math number theory Statement B Codeforces Round 447 (Div. 2) {894} PROGRAMMING Codeforces Round #447 (Div.2 Only) Editorial 1800
14147 New Year's Eve bitmasks constructive algorithms number theory Statement B Codeforces Round 456 (Div. 2) {912} PROGRAMMING Codeforces Round #456 (Div. 2) Editorial 1400
759 Divisibility constructive algorithms dp greedy number theory Statement F Codeforces Round 461 (Div. 2) {922} PROGRAMMING 57605 2500
3284 Mahmoud and Ehab and another array construction task constructive algorithms greedy math number theory Statement D Codeforces Round 473 (Div. 2) {959} PROGRAMMING Codeforces round #473 editorial 2000
2840 Missing Numbers binary search constructive algorithms greedy math number theory Statement E Avito Cool Challenge 2018 {1081} PROGRAMMING 63888 1900
10081 Meaningless Operations constructive algorithms math number theory Statement C Codeforces Global Round 1 {1110} PROGRAMMING The Editorial of the First Codeforces Global Round 1500
2234 Cooperative Game constructive algorithms interactive number theory Statement D Codeforces Round 545 (Div. 1) {1137} PROGRAMMING Codeforces Round #545 – Editorial 2500
568 Gold Experience constructive algorithms graphs math number theory probabilities Statement G Codeforces Global Round 3 {1148} PROGRAMMING Codeforces Global Round 3 Editorial 3100
18130 Prefix Sum Primes constructive algorithms greedy math number theory Statement A Codeforces Round 556 (Div. 1) {1149} PROGRAMMING 66783 1300
11958 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
3032 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
12847 Ehab and a Special Coloring Problem constructive algorithms number theory Statement C Codeforces Round 563 (Div. 2) {1174} PROGRAMMING Codeforces round #563 editorial 1300
7961 Prime Graph constructive algorithms greedy math number theory Statement D Codeforces Global Round 4 {1178} PROGRAMMING E 1600
665 To Make 1 bitmasks constructive algorithms dp greedy number theory Statement G Technocup 2020 - Elimination Round 2 {1225} PROGRAMMING 70898 3000
13315 Tile Painting constructive algorithms math number theory Statement A Codeforces Round 599 (Div. 1) {1242} PROGRAMMING Codeforces Round #599 Editorial 1500
5056 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
3532 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
1131 Beautiful Fibonacci Problem constructive algorithms number theory Statement F Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 3600
10095 Diverse Matrix constructive algorithms greedy math number theory Statement C Codeforces Global Round 6 {1266} PROGRAMMING Codeforces Global Round 6 Editorial 1400
13778 Ehab the Xorcist bitmasks constructive algorithms greedy number theory Statement D Codeforces Round 628 (Div. 2) {1325} PROGRAMMING 1750.0 74235 1700
46960 EhAb AnD gCd constructive algorithms greedy number theory Statement A Codeforces Round 628 (Div. 2) {1325} PROGRAMMING 500.0 74235 800
32922 Bad Ugly Numbers constructive algorithms number theory Statement A Codeforces Global Round 7 {1326} PROGRAMMING 500.0 74961 1000
19273 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
981 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
8392 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
12562 Two Divisors constructive algorithms math number theory Statement D Educational Codeforces Round 89 (Rated for Div. 2) {1366} PROGRAMMING Educational Codeforces Round 89 Editorial
25246 GCD Compression brute force constructive algorithms math number theory Statement B Codeforces Round 651 (Div. 2) {1370} PROGRAMMING 1000.0 Editorial — Codeforces Round #651
37690 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
2985 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
51080 LCM Problem constructive algorithms greedy math number theory Statement A Educational Codeforces Round 92 (Rated for Div. 2) {1389} PROGRAMMING 80809
16803 Multiples of Length constructive algorithms greedy number theory Statement A Codeforces Round 666 (Div. 1) {1396} PROGRAMMING 500.0 Codeforces Round #666 — Editorial
10716 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
27190 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
1302 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
3542 Decryption bitmasks constructive algorithms implementation math number theory Statement E Codeforces Round 671 (Div. 2) {1419} PROGRAMMING 2250.0 Codeforces Round #671 Editorial
1676 Xum bitmasks constructive algorithms math number theory Statement E Codeforces Global Round 11 {1427} PROGRAMMING 1500.0 Editorial of Global Round 11 2500
22494 Number into Sequence constructive algorithms math number theory Statement D Codeforces Round 686 (Div. 3) {1454} PROGRAMMING Codeforces Round #686 (Div. 3) Editorial
10265 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
42131 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
6599 Nezzar and Board constructive algorithms math number theory Statement A Codeforces Round 698 (Div. 1) {1477} PROGRAMMING 500.0 87294 1800
5713 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
24870 GCD Length constructive algorithms math number theory Statement B Educational Codeforces Round 107 (Rated for Div. 2) {1511} PROGRAMMING 89634
6640 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
18694 Product 1 Modulo N constructive algorithms math number theory Statement C Codeforces Round 716 (Div. 2) {1514} PROGRAMMING 1500.0 Codeforces round #716 editorial
15477 Another Problem About Dividing Numbers constructive algorithms number theory Statement D Codeforces Round 725 (Div. 3) {1538} PROGRAMMING Codeforces Round #725 (Div. 3) Editorial
26849 Plus and Multiply constructive algorithms math number theory Statement B Codeforces Round 729 (Div. 2) {1542} PROGRAMMING 1250.0
7142 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
176 Xor-quiz constructive algorithms dp interactive math number theory Statement H Codeforces Global Round 16 {1566} PROGRAMMING 3750.0 Codeforces Global Round 16 Editorial
17930 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
15179 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
933 Quadratic Set constructive algorithms hashing number theory Statement F Educational Codeforces Round 120 (Rated for Div. 2) {1622} PROGRAMMING Educational Codeforces Round 120 Editorial
16416 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
7629 K-good constructive algorithms games math number theory Statement D CodeTON Round 1 (Div. 1 + Div. 2, Rated, Prizes!) {1656} PROGRAMMING 2000.0 Tutorial
4738 GCD Guess bitmasks chinese remainder theorem constructive algorithms interactive math number theory Statement D Codeforces Round 781 (Div. 2) {1665} PROGRAMMING 1500.0 Codeforces Round #781 (Div. 2) Editorial
811 Euclid Guess constructive algorithms flows graph matchings math number theory Statement G Codeforces Round 792 (Div. 1 + Div. 2) {1684} PROGRAMMING 2500.0 Codeforces Round #792 (Div. 1 + Div. 2) Editorial 2800
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
9575 Equate Multisets constructive algorithms data structures graph matchings greedy math number theory Statement F Codeforces Round 805 (Div. 3) {1702} PROGRAMMING 104763
7789 Chopping Carrots (Easy Version) binary search brute force constructive algorithms dp greedy number theory Statement D1 Codeforces Round 809 (Div. 2) {1706} PROGRAMMING 1000.0 Codeforces Round #809 Editorial
1963 Chopping Carrots (Hard Version) constructive algorithms dp number theory two pointers Statement D2 Codeforces Round 809 (Div. 2) {1706} PROGRAMMING 1250.0 Codeforces Round #809 Editorial
186 Bugaboo bitmasks constructive algorithms dp number theory Statement F Codeforces Round 808 (Div. 1) {1707} PROGRAMMING 3250.0 104930
22455 Woeful Permutation constructive algorithms greedy number theory Statement B Codeforces Round 813 (Div. 2) {1712} PROGRAMMING 1000.0 Codeforces Round #813 (Div. 2) Editorial
6295 Tournament Countdown constructive algorithms fft greedy greedy interactive number theory probabilities Statement D Codeforces Round 812 (Div. 2) {1713} PROGRAMMING 2000.0 Codeforces Round #812 (Div. 2) Editorial 1800
17760 Bestie brute force constructive algorithms implementation math number theory Statement A Codeforces Round 830 (Div. 2) {1732} PROGRAMMING 750.0 108327 1000
3304 Rectangular Congruence constructive algorithms math number theory Statement E Codeforces Round 822 (Div. 2) {1734} PROGRAMMING 2250.0 Codeforces Round #822 (Div.2) Editorial
162 Ela and Prime GCD constructive algorithms math number theory Statement F Dytechlab Cup 2022 {1737} PROGRAMMING 3500.0 Editorial of Dytechlab Cup 2022
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
18727 Make Array Good constructive algorithms implementation number theory sortings Statement B Codeforces Round 838 (Div. 2) {1762} PROGRAMMING 1000.0 Codeforces Round #838 (Div. 2) Editorial
19011 Candies constructive algorithms math number theory Statement B CodeTON Round 4 (Div. 1 + Div. 2, Rated, Prizes!) {1810} PROGRAMMING 750.0 Editorial of CodeTON Round 4 (Div. 1 + Div. 2, Rated, Prizes!)
4947 Trivial Conjecture *special constructive algorithms math number theory Statement D April Fools Day Contest 2023 {1812} PROGRAMMING Editorial of April Fools Day Contest 2023
17566 No Prime Differences constructive algorithms math number theory Statement C Codeforces Round 877 (Div. 2) {1838} PROGRAMMING 1250.0 Codeforces Round #877 (Div. 2) Editorial
1202 Tree Weights bitmasks constructive algorithms data structures dfs and similar math matrices number theory trees Statement G Codeforces Round 884 (Div. 1 + Div. 2) {1844} PROGRAMMING 3500.0 Codeforces Round #884 (Div. 1 + Div. 2) Editorial
13946 Row Major constructive algorithms math number theory strings Statement D Codeforces Round 884 (Div. 1 + Div. 2) {1844} PROGRAMMING 1500.0 Codeforces Round #884 (Div. 1 + Div. 2) Editorial
25712 Yet Another Permutation Problem constructive algorithms math number theory Statement C Codeforces Round 893 (Div. 2) {1858} PROGRAMMING 1500.0 Codeforces Round #893 (Div. 2) Editorial 1000
15452 Divisor Chain bitmasks constructive algorithms math number theory Statement C Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) {1864} PROGRAMMING 1250.0 Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Editorial
1247 Two Permutations (Easy Version) brute force constructive algorithms greedy number theory Statement E1 Codeforces Round 899 (Div. 2) {1882} PROGRAMMING 2000.0 Codeforces Round 899 (Div. 2) Editorial
17441 Insert and Equalize brute force constructive algorithms greedy math number theory Statement C Educational Codeforces Round 159 (Rated for Div. 2) {1902} PROGRAMMING Educational Codeforces Round 159 Editorial
1727 Multiple Lamps brute force constructive algorithms number theory Statement E Pinely Round 3 (Div. 1 + Div. 2) {1909} PROGRAMMING 2500.0 Editorial of Pinely Round 3 (Div. 1 + Div. 2)
28466 2023 constructive algorithms implementation math number theory Statement A Good Bye 2023 {1916} PROGRAMMING 250.0
32658 Two Divisors constructive algorithms math number theory Statement B Good Bye 2023 {1916} PROGRAMMING 750.0
2221 Modular Sequence constructive algorithms dp greedy implementation math number theory Statement E Codeforces Round 924 (Div. 2) {1928} PROGRAMMING 2250.0 Codeforces Round 924 Editorial
3782 One-Dimensional Puzzle combinatorics constructive algorithms math number theory Statement G Codeforces Round 925 (Div. 3) {1931} PROGRAMMING 125878
23869 Turtle Tenacity: Continual Mods constructive algorithms greedy number theory sortings Statement D Codeforces Round 929 (Div. 3) {1933} PROGRAMMING Codeforces Round 929 (Div. 3) Editorial
8263 Missing Subsequence Sum bitmasks constructive algorithms greedy number theory Statement B Codeforces Round 941 (Div. 1) {1965} PROGRAMMING 1250.0 Codeforces Round #941 (Div. 1, Div. 2) Editorial 1800
29601 Assembly via Remainders constructive algorithms number theory Statement C Codeforces Round 943 (Div. 3) {1968} PROGRAMMING 129096 1000
22454 Earning on Bets binary search combinatorics constructive algorithms number theory Statement C Codeforces Round 951 (Div. 2) {1979} PROGRAMMING 1500.0 Codeforces Round 951 (Div. 2) Editorial
2208 Turtle and Multiplication constructive algorithms dfs and similar graphs number theory Statement D Codeforces Round 949 (Div. 2) {1981} PROGRAMMING 2000.0 Simplified Chinese Tutorial
7978 Prime XOR Coloring bitmasks constructive algorithms graphs greedy math number theory Statement D Pinely Round 4 (Div. 1 + Div. 2) {1991} PROGRAMMING 1500.0 Video Tutorial
1213 Dyn-scripted Robot (Easy Version) brute force chinese remainder theorem constructive algorithms math number theory Statement F1 Codeforces Round 963 (Div. 2) {1993} PROGRAMMING 2500.0 Editorial of Codeforces Round 963 (Div. 2)
7690 Funny Game constructive algorithms dsu graphs greedy math number theory Statement D Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} PROGRAMMING 2000.0 Video Tutorial
10420 Squaring brute force constructive algorithms data structures greedy implementation math number theory Statement C Codeforces Round 961 (Div. 2) {1995} PROGRAMMING 1750.0 Video Tutorial
28470 Minimize Equal Sum Subarrays constructive algorithms math number theory Statement B Codeforces Round 965 (Div. 2) {1998} PROGRAMMING 750.0 Video Tutorial
3591 Common Generator brute force constructive algorithms greedy math number theory Statement E Refact.ai Match 1 (Codeforces Round 985) {2029} PROGRAMMING 2500.0 Refact.ai Match 1 (Codeforces Round 985) Editorial
15954 Penchick and BBQ Buns brute force constructive algorithms math number theory Statement C Codeforces Round 987 (Div. 2) {2031} PROGRAMMING 1500.0 Codeforces Round 987 (Div. 2) Editorial
20872 Everyone Loves Tres constructive algorithms greedy math number theory Statement B Codeforces Global Round 27 {2035} PROGRAMMING 500.0 Codeforces Global Round 27 Editorial
25941 Superultra's Favorite Permutation constructive algorithms greedy math number theory Statement C Codeforces Round 988 (Div. 3) {2037} PROGRAMMING Video Tutorial
7137 Shohag Loves GCD constructive algorithms greedy math number theory Statement D CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} PROGRAMMING 2000.0 Editorial of CodeTON Round 9 (Div. 1 + Div. 2)
18234 Shohag Loves Mod constructive algorithms number theory Statement A CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} PROGRAMMING 500.0 Editorial of CodeTON Round 9 (Div. 1 + Div. 2)
5933 Non Prime Tree brute force constructive algorithms dfs and similar greedy number theory trees two pointers Statement D Codeforces Round 992 (Div. 2) {2040} PROGRAMMING 2000.0 Codeforces Round #992 (Div.2) Editorial
8652 Goodbye, Banker Life bitmasks combinatorics constructive algorithms math number theory Statement F Codeforces Round 1006 (Div. 3) {2072} PROGRAMMING Codeforces Round 1006 (Div. 3) Editorial
1224 MST in Modulo Graph constructive algorithms dsu graphs greedy math number theory sortings Statement D Codeforces Round 1010 (Div. 1, Unrated) {2081} PROGRAMMING 1750.0 Codeforces Round 1010 (Div. 1, Div. 2, based on Zhili Cup 2025) Editorial
3206 Serval and Modulo brute force constructive algorithms math number theory Statement E Codeforces Round 1011 (Div. 2) {2085} PROGRAMMING 2500.0 Codeforces Round #1011 (Div. 2) Editorial
23859 Serval and String Theory constructive algorithms implementation Statement A Codeforces Round 1011 (Div. 2) {2085} PROGRAMMING 500.0 Codeforces Round #1011 (Div. 2) Editorial
7394 Simple Permutation constructive algorithms number theory Statement A Codeforces Round 1012 (Div. 1) {2089} PROGRAMMING 750.0 Codeforces Round 1012 (Div.1, Div. 2, based on THUPC 2025 — Finals) Editorial
437 Andryusha and CCB brute force constructive algorithms greedy math number theory strings Statement F Codeforces Round 1014 (Div. 2) {2092} PROGRAMMING 3000.0 Codeforces Round #1014 (Div. 2) Editorial
1049 Bermuda Triangle chinese remainder theorem constructive algorithms geometry math number theory Statement C Codeforces Round 1021 (Div. 1) {2097} PROGRAMMING 1500.0 142316
11723 Hacking Numbers (Easy Version) bitmasks constructive algorithms interactive math number theory Statement C1 Codeforces Round 1025 (Div. 2) {2109} PROGRAMMING 1250.0 Codeforces Round 1025 (Div. 2) Editorial
8890 Hacking Numbers (Medium Version) constructive algorithms interactive math number theory Statement C2 Codeforces Round 1025 (Div. 2) {2109} PROGRAMMING 750.0 Codeforces Round 1025 (Div. 2) Editorial
3317 Hacking Numbers (Hard Version) constructive algorithms interactive math number theory Statement C3 Codeforces Round 1025 (Div. 2) {2109} PROGRAMMING 500.0 Codeforces Round 1025 (Div. 2) Editorial
15976 Gellyfish and Flaming Peony brute force constructive algorithms dp greedy math number theory shortest paths Statement A Codeforces Round 1028 (Div. 1) {2115} PROGRAMMING 500.0 Codeforces Round 1028 (Div.1, Div.2) Editorial
10027 Minimize Fixed Points constructive algorithms number theory Statement F Codeforces Round 1034 (Div. 3) {2123} PROGRAMMING Codeforces Round 1034 (Div. 3) Editorial
906 Sea, You & copriMe brute force combinatorics constructive algorithms graphs greedy math number theory Statement H Codeforces Round 1042 (Div. 3) {2131} PROGRAMMING Codeforces Round 1042 (Div. 3) Editorial
21820 Add 0 or K constructive algorithms math number theory Statement B Codeforces Round 1045 (Div. 2) {2134} PROGRAMMING 1250.0 145832
27262 Fun Permutation constructive algorithms math number theory Statement B Codeforces Round 1047 (Div. 3) {2137} PROGRAMMING Codeforces Round 1047 (Div. 3) Editorial
23102 Another Divisibility Problem constructive algorithms math number theory Statement B Codeforces Round 1049 (Div. 2) {2140} PROGRAMMING 1000.0 Codeforces Round 1049 (Div. 2) Editorial
287 Distinct GCDs (Hard Version) combinatorics constructive algorithms graphs graphs graphs math number theory number theory Statement F2 Codeforces Round 1067 (Div. 2) {2158} PROGRAMMING 1000.0 Codeforces Round 1067 (Div. 2) Editorial
449 Distinct GCDs (Easy Version) constructive algorithms constructive algorithms graphs graphs number theory number theory Statement F1 Codeforces Round 1067 (Div. 2) {2158} PROGRAMMING 2500.0 Codeforces Round 1067 (Div. 2) Editorial
2366 Removal of a Sequence (Hard Version) binary search constructive algorithms divide and conquer greedy implementation math number theory probabilities Statement D2 Educational Codeforces Round 184 (Rated for Div. 2) {2169} PROGRAMMING Educational Codeforces Round 184 Editorial
3765 Anisphia Wynn Palettia and Good Permutations constructive algorithms greedy number theory Statement E Codeforces Round 1065 (Div. 3) {2171} PROGRAMMING Codeforces Round 1065 (Div. 3) Editorial
6691 XOR-factorization bitmasks constructive algorithms dp greedy number theory Statement C Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} PROGRAMMING 1500.0 Codeforces Global Round 31
24321 A Simple Sequence constructive algorithms dp greedy number theory Statement A Codeforces Round 1089 (Div. 2) {2210} PROGRAMMING 500.0 Codeforces Round 1089 (Div. 2) Editorial
361 Binary Strings are Simple? constructive algorithms dsu interactive number theory Statement E Codeforces Round 1089 (Div. 2) {2210} PROGRAMMING 2750.0 Codeforces Round 1089 (Div. 2) Editorial
769 Quadratic Jumps constructive algorithms greedy math number theory Statement F Codeforces Round 1099 (Div. 2) {2231} PROGRAMMING 2750.0
8422 XOR, Expression and Two Binary Numbers bitmasks constructive algorithms math number theory Statement D Codeforces Round 1102 (Div. 2) {2234} PROGRAMMING 1750.0
10130 Yaroslav and Productivity constructive algorithms dp greedy math number theory Statement D Codeforces Round 1109 (Div. 3) {2244} PROGRAMMING
13921 Stepan and Permutation constructive algorithms dsu greedy math number theory sortings Statement C Codeforces Round 1109 (Div. 3) {2244} PROGRAMMING
14110 ezraft and Array constructive algorithms number theory Statement B Codeforces Round 1108 (Div. 2) {2246} PROGRAMMING 750.0