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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 15378 | Bear and Prime 100 | constructive algorithms interactive math | Statement | A | Codeforces Round 356 (Div. 1) {679} | PROGRAMMING | Codeforces Round #356 — Editorial | 1400 | |
| 1503 | Searching Rectangles | binary search constructive algorithms interactive | Statement | B | Codeforces Round 371 (Div. 1) {713} | PROGRAMMING | Codeforces Round #371 Editorial | 2200 | |
| 8913 | Guess the Array | constructive algorithms interactive math | Statement | C | Technocup 2017 - Elimination Round 1 (Unofficially Open for Everyone, Rated for Div. 2) {727} | PROGRAMMING | Tutorial | 1400 | |
| 2771 | Minimum and Maximum | constructive algorithms interactive | Statement | B | 2016-2017 ACM-ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) {730} | PROGRAMMING | Разбор задач (видео, по-русски) | 1900 | |
| 592 | New Year and Finding Roots | constructive algorithms implementation interactive trees | Statement | F | Good Bye 2016 {750} | PROGRAMMING | Good Bye 2016 — hints and codes | 2700 | |
| 1434 | Interactive Bulls and Cows (Easy) | brute force constructive algorithms implementation | Statement | B | Testing Round 13 {753} | PROGRAMMING | 1600 | ||
| 396 | Interactive Bulls and Cows (Hard) | brute force constructive algorithms interactive | Statement | C | Testing Round 13 {753} | PROGRAMMING | 2400 | ||
| 409 | Finding lines | constructive algorithms divide and conquer interactive | Statement | D | Codeforces Round 407 (Div. 1) {788} | PROGRAMMING | Codeforces Round #407(Div.1 + Div.2) Editorial | 2900 | |
| 1900 | Vladik and Favorite Game | constructive algorithms dfs and similar graphs interactive | Statement | D | Codeforces Round 416 (Div. 2) {811} | PROGRAMMING | 2000 | ||
| 1346 | The penguin's game | binary search constructive algorithms interactive | Statement | E | Codeforces Round 427 (Div. 2) {835} | PROGRAMMING | 2400 | ||
| 2294 | Ithea Plays With Chtholly | binary search constructive algorithms games greedy interactive | Statement | B | Codeforces Round 449 (Div. 1) {896} | PROGRAMMING | Codeforces Round #449 Editorial | 2000 | |
| 2217 | Down or Right | constructive algorithms interactive matrices | Statement | E | Codeforces Round 504 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1023} | PROGRAMMING | Codeforces Round 504 Editorial | 2100 | |
| 787 | Hidden Bipartite Graph | binary search constructive algorithms dfs and similar graphs interactive | Statement | E | Lyft Level 5 Challenge 2018 - Elimination Round {1033} | PROGRAMMING | The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial | 2700 | |
| 3275 | Dwarves, Hats and Extrasensory Abilities | binary search constructive algorithms geometry interactive | Statement | C | Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} | PROGRAMMING | 1900 | ||
| 505 | Tricky Interactor | constructive algorithms implementation interactive | Statement | F | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 2500 | |
| 3160 | Ehab and another another xor problem | bitmasks constructive algorithms implementation interactive | Statement | D | Codeforces Round 525 (Div. 2) {1088} | PROGRAMMING | Codeforces round #525 editorial | 2000 | |
| 915 | Dasha and Chess | constructive algorithms games interactive | Statement | D | Codeforces Round 532 (Div. 2) {1100} | PROGRAMMING | Unofficial Tutorial | 2400 | |
| 3521 | Game with modulo | binary search constructive algorithms interactive | Statement | B | Codeforces Round 534 (Div. 1) {1103} | PROGRAMMING | Codeforces Round #534 — Editorial | 2000 | |
| 1635 | Decypher the String | bitmasks chinese remainder theorem constructive algorithms interactive math | Statement | E | Educational Codeforces Round 60 (Rated for Div. 2) {1117} | PROGRAMMING | 65365 | 2200 | |
| 2141 | Cooperative Game | constructive algorithms interactive number theory | Statement | D | Codeforces Round 545 (Div. 1) {1137} | PROGRAMMING | Codeforces Round #545 – Editorial | 2500 | |
| 1956 | Ehab and the Big Finale | constructive algorithms divide and conquer graphs implementation interactive trees | Statement | F | Codeforces Round 563 (Div. 2) {1174} | PROGRAMMING | Codeforces round #563 editorial | 2300 | |
| 1591 | Point Ordering | constructive algorithms geometry interactive math | Statement | C | Codeforces Round 601 (Div. 1) {1254} | PROGRAMMING | Codeforces Round #601 Editorial | 2300 | |
| 1068 | Intriguing Selection | brute force constructive algorithms implementation interactive sortings | Statement | I | 2019-2020 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1267} | PROGRAMMING | nerc-2019-tutorial.pdf | 2700 | |
| 4862 | Strange Device | constructive algorithms interactive math sortings | Statement | D | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 1900 | |
| 2371 | Enchanted Artifact | constructive algorithms interactive strings | Statement | D | Codeforces Round 610 (Div. 2) {1282} | PROGRAMMING | 72461 | 2300 | |
| 1577 | Madhouse (Easy version) | brute force constructive algorithms interactive math | Statement | C1 | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 2400 | |
| 744 | Madhouse (Hard version) | brute force constructive algorithms hashing interactive math | Statement | C2 | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 2900 | |
| 947 | Coffee Varieties (hard version) | constructive algorithms graphs interactive | Statement | D | Codeforces Round 616 (Div. 1) {1290} | PROGRAMMING | 2500.0 | Codeforces Round #616 Editorial | 2900 |
| 462 | Rin and The Unknown Flower | constructive algorithms greedy interactive math | Statement | E | Codeforces Round 614 (Div. 1) {1292} | PROGRAMMING | 2250.0 | Codeforces Round #614 Editorial | 3500 |
| 5354 | Kuroni and the Celebration | constructive algorithms dfs and similar graphs interactive trees | Statement | D | Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} | PROGRAMMING | 1750.0 | Ozon Tech Challenge 2020 Editorial | 1900 |
| 524 | Yui and Mahjong Set | constructive algorithms interactive | Statement | D | Codeforces Round 635 (Div. 1) {1336} | PROGRAMMING | 2250.0 | Codeforces Round #635 Editorial | 3000 |
| 959 | Guess Divisors Count | constructive algorithms interactive number theory | Statement | F | Codeforces Round 643 (Div. 2) {1355} | PROGRAMMING | 3000.0 | Codeforces Round #643 (Div. 2) Editorial | 2600 |
| 1546 | X-OR | bitmasks constructive algorithms interactive probabilities | Statement | E | Codeforces Round 649 (Div. 2) {1364} | PROGRAMMING | 2500.0 | Codeforces round #649 editorial | 2700 |
| 1413 | Secure Password | bitmasks combinatorics constructive algorithms interactive math | Statement | G | Codeforces Round 648 (Div. 2) {1365} | PROGRAMMING | 3000.0 | Editorial — Codeforces Round #648 | 2800 |
| 2502 | Integer Game | brute force constructive algorithms games interactive math | Statement | F | Codeforces Global Round 9 {1375} | PROGRAMMING | 2000.0 | 79731 | |
| 349 | Colors | *special binary search constructive algorithms interactive | Statement | A | Baltic Olympiad in Informatics 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1386} | PROGRAMMING | T | ||
| 3736 | Omkar and Duck | bitmasks constructive algorithms interactive math | Statement | E | Codeforces Global Round 10 {1392} | PROGRAMMING | 2000.0 | Codeforces Global Round 10 — Editorial | |
| 1269 | Game of Pairs | constructive algorithms dfs and similar interactive math number theory | Statement | D | Codeforces Round 668 (Div. 1) {1404} | PROGRAMMING | 2250.0 | Codeforces Round #668 Editorial | |
| 14616 | Chocolate Bunny | constructive algorithms interactive math two pointers | Statement | C | Codeforces Round 669 (Div. 2) {1407} | PROGRAMMING | 1500.0 | Codeforces Round #669 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 | |
| 1436 | Strange Shuffle | binary search brute force constructive algorithms interactive probabilities | Statement | C | Codeforces Round 694 (Div. 1) {1470} | PROGRAMMING | 1000.0 | 86464 | |
| 1130 | Magnets | binary search constructive algorithms interactive | Statement | F | Codeforces Global Round 13 {1491} | PROGRAMMING | 2000.0 | Codeforces Global Round 13 Editorial | |
| 7667 | 3-Coloring | constructive algorithms games interactive | Statement | B | Codeforces Round 712 (Div. 1) {1503} | PROGRAMMING | 1000.0 | T | 1700 |
| 4603 | Nastia and a Hidden Permutation | constructive algorithms interactive | Statement | C | Codeforces Round 720 (Div. 2) {1521} | PROGRAMMING | 1750.0 | 90477 | |
| 388 | Median Queries | constructive algorithms interactive probabilities | Statement | F | Codeforces Round 723 (Div. 2) {1526} | PROGRAMMING | 3500.0 | Codeforces Round #723 (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 | |
| 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 | |
| 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 |
| 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 |
| 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 | |
| 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) | ||
| 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) | |
| 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) | |
| 3777 | Interacdive Problem | binary search constructive algorithms interactive | Statement | F | Codeforces Round 764 (Div. 3) {1624} | PROGRAMMING | Codeforces Round #764 (Div. 3) Editorial | ||
| 3569 | Grid Xor | constructive algorithms greedy implementation interactive math | Statement | C | Codeforces Round 767 (Div. 1) {1628} | PROGRAMMING | 1250.0 | 99276 | |
| 4714 | Finding Zero | constructive algorithms greedy interactive | Statement | D | Codeforces Round 770 (Div. 2) {1634} | PROGRAMMING | 2000.0 | Codeforces Round #770 (Div. 2) editorial | |
| 4625 | 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 | |
| 2514 | notepad.exe | binary search constructive algorithms greedy interactive | Statement | E | Codeforces Global Round 20 {1672} | PROGRAMMING | 1500.0 | Global Round 20 Editorial | 2200 |
| 954 | Anti-Theft Road Planning | bitmasks constructive algorithms divide and conquer greedy interactive math | Statement | F | Codeforces Round 785 (Div. 2) {1673} | PROGRAMMING | 3250.0 | Codeforces Round #785 (Div. 2) Editorial | |
| 4131 | Railway System | constructive algorithms dsu graphs greedy interactive sortings | Statement | B | Codeforces Round 796 (Div. 1) {1687} | PROGRAMMING | 750.0 | Editorial of Codeforces Round 796 | |
| 4982 | Guess The String | binary search brute force constructive algorithms dsu interactive | Statement | D | Educational Codeforces Round 130 (Rated for Div. 2) {1697} | PROGRAMMING | 103835 | ||
| 12020 | Fixed Point Guessing | binary search constructive algorithms interactive | Statement | D | Codeforces Round 803 (Div. 2) {1698} | PROGRAMMING | 1500.0 | Codeforces Round #803 (Div. 2) Editorial | |
| 692 | Mark and the Online Exam | bitmasks constructive algorithms interactive math probabilities | Statement | F | Codeforces Round 807 (Div. 2) {1705} | PROGRAMMING | 3000.0 | Codeforces Round #807 (Div 2.) Editorial | |
| 6219 | 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 |
| 588 | Crop Squares | constructive algorithms geometry interactive math | Statement | F | Codeforces Round 816 (Div. 2) {1715} | PROGRAMMING | 3000.0 | Codeforces Round #816 (Div. 2) editorial | |
| 1373 | Connectivity Addicts | constructive algorithms dsu graphs greedy interactive shortest paths sortings trees | Statement | F | Codeforces Global Round 22 {1738} | PROGRAMMING | 2750.0 | Editorial of Codeforces Global Round <strong>22</strong> | |
| 1688 | Joking (Easy Version) | binary search bitmasks constructive algorithms interactive ternary search | Statement | E1 | Codeforces Global Round 23 {1746} | PROGRAMMING | 2000.0 | Codeforces Global Round 23 Editorial | |
| 2025 | Anya's Simultaneous Exhibition | constructive algorithms data structures graphs greedy interactive sortings | Statement | E | Hello 2023 {1779} | PROGRAMMING | 2250.0 | ||
| 8903 | Li Hua and Chess | brute force constructive algorithms greedy hashing interactive | Statement | C | Codeforces Round 864 (Div. 2) {1797} | PROGRAMMING | 1500.0 | Codeforces Round 864 (Div. 2) Editorial | |
| 3593 | Sum Graph | constructive algorithms graphs implementation interactive math shortest paths trees | Statement | B | Codeforces Round 865 (Div. 1) {1815} | PROGRAMMING | 1250.0 | Editorial of Codeforces Round #865 | 2000 |
| 1533 | Decreasing Game | constructive algorithms dp greedy interactive | Statement | E | Codeforces Round 876 (Div. 2) {1839} | PROGRAMMING | 2750.0 | Codeforces Round #876 (Div. 2) Editorial | |
| 2781 | In Search of Truth (Easy Version) | brute force constructive algorithms interactive math probabilities | Statement | G1 | Codeforces Round 878 (Div. 3) {1840} | PROGRAMMING | Codeforces Round #878 (Div.3) Editorial | ||
| 1180 | In Search of Truth (Hard Version) | constructive algorithms interactive math probabilities | Statement | G2 | Codeforces Round 878 (Div. 3) {1840} | PROGRAMMING | Codeforces Round #878 (Div.3) Editorial | ||
| 3709 | Rudolph and Mimic | constructive algorithms greedy implementation interactive | Statement | F | Codeforces Round 883 (Div. 3) {1846} | PROGRAMMING | |||
| 12654 | Salyg1n and the MEX Game | constructive algorithms data structures games greedy interactive | Statement | C | Codeforces Round 897 (Div. 2) {1867} | PROGRAMMING | 1250.0 | ||
| 4323 | Salyg1n and Array (simple version) | constructive algorithms interactive math | Statement | E1 | Codeforces Round 897 (Div. 2) {1867} | PROGRAMMING | 2000.0 | ||
| 3747 | Salyg1n and Array (hard version) | constructive algorithms interactive math | Statement | E2 | Codeforces Round 897 (Div. 2) {1867} | PROGRAMMING | 1000.0 | ||
| 1565 | Interactive Game with Coloring | brute force constructive algorithms graphs implementation interactive math trees | Statement | E | Educational Codeforces Round 155 (Rated for Div. 2) {1879} | PROGRAMMING | 120773 | 2400 | |
| 492 | Good Colorings | binary search constructive algorithms graphs interactive | Statement | E | Codeforces Round 905 (Div. 1) {1887} | PROGRAMMING | 2000.0 | Codeforces Round #905 (Div. 1, Div. 2, Div. 3) Editorial | |
| 409 | Pepe Racing | constructive algorithms interactive sortings | Statement | G | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) {1896} | PROGRAMMING | 3250.0 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 2503 | Geo Game | constructive algorithms dp games greedy interactive math | Statement | E | Codeforces Round 912 (Div. 2) {1903} | PROGRAMMING | 2250.0 | Codeforces Round #912 (Div. 2) Editorial | |
| 225 | Anti-Proxy Attendance | constructive algorithms interactive ternary search | Statement | F | Codeforces Round 921 (Div. 1) {1924} | PROGRAMMING | 3000.0 | Codeforces Round 921 (Div. 1, Div. 2) Editorial | |
| 8057 | Find a Mine | constructive algorithms geometry greedy interactive math | Statement | C | Codeforces Round 931 (Div. 2) {1934} | PROGRAMMING | 1500.0 | Tutorial | |
| 8637 | Bitwise Operation Wizard | bitmasks constructive algorithms greedy interactive math | Statement | A | Codeforces Round 930 (Div. 1) {1936} | PROGRAMMING | 500.0 | Codeforces Round 930 (Div. 1, Div. 2) Editorial | |
| 30 | Draw Polygon Lines | *special constructive algorithms dp geometry interactive | Statement | A | XVIII Open Olympiad in Informatics - Final Stage, Day 1 (Unrated, Online Mirror, IOI rules) {1939} | PROGRAMMING | |||
| 937 | Arithmancy (Easy) | brute force constructive algorithms interactive strings | Statement | D1 | Helvetic Coding Contest 2024 online mirror (teams allowed, unrated) {1970} | PROGRAMMING | Helvetic Coding Contest 2024 Editorial | 2100 | |
| 308 | Arithmancy (Medium) | constructive algorithms interactive probabilities strings | Statement | D2 | Helvetic Coding Contest 2024 online mirror (teams allowed, unrated) {1970} | PROGRAMMING | Helvetic Coding Contest 2024 Editorial | 2600 | |
| 933 | Tensor | constructive algorithms graphs interactive | Statement | E | Codeforces Round 948 (Div. 2) {1977} | PROGRAMMING | 2500.0 | 129858 | 2600 |
| 1135 | Catch the Mole(Easy Version) | binary search constructive algorithms data structures interactive trees | Statement | E1 | Codeforces Round 960 (Div. 2) {1990} | PROGRAMMING | 2000.0 | Video Tutorial | |
| 5101 | Coloring Game | constructive algorithms games graphs greedy interactive | Statement | E | Pinely Round 4 (Div. 1 + Div. 2) {1991} | PROGRAMMING | 2000.0 | Video Tutorial | |
| 171 | Grid Game | constructive algorithms games greedy interactive | Statement | I | Pinely Round 4 (Div. 1 + Div. 2) {1991} | PROGRAMMING | 4000.0 | Video Tutorial | |
| 14481 | Password Cracking | brute force constructive algorithms interactive strings | Statement | C | Codeforces Round 973 (Div. 2) {2013} | PROGRAMMING | 1250.0 | 134298 | |
| 3984 | Asesino (Easy Version) | binary search constructive algorithms implementation interactive | Statement | D1 | Codeforces Round 978 (Div. 2) {2022} | PROGRAMMING | 1750.0 | Codeforces Round 978 (Div 2) Editorial | |
| 449 | Penchick and Even Medians | binary search constructive algorithms interactive | Statement | F | Codeforces Round 987 (Div. 2) {2031} | PROGRAMMING | 3000.0 | Codeforces Round 987 (Div. 2) Editorial | |
| 6175 | Genokraken | binary search constructive algorithms data structures graphs interactive trees two pointers | Statement | D | Codeforces Round 983 (Div. 2) {2032} | PROGRAMMING | 1750.0 | Codeforces Round 983 (Div. 2) Editorial | |
| 1660 | Library of Magic | binary search bitmasks constructive algorithms interactive | Statement | G | Codeforces Round 984 (Div. 3) {2036} | PROGRAMMING | Codeforces Round 984 (Div. 3) Editorial | ||
| 2944 | Guess One Character | constructive algorithms interactive | Statement | G | 2024-2025 ICPC, NERC, Southern and Volga Russian Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2038} | PROGRAMMING | 1900 | ||
| 717 | Secret Message | constructive algorithms math | Statement | G | Hello 2025 {2057} | PROGRAMMING | 3750.0 | ||
| 489 | Kevin and Teams | constructive algorithms graphs interactive | Statement | G | IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) {2061} | PROGRAMMING | 3000.0 | IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) Editorial | |
| 3642 | Finding OR Sum | bitmasks constructive algorithms implementation interactive math | Statement | B | Codeforces Round 1008 (Div. 1) {2077} | PROGRAMMING | 1000.0 | Codeforces Round 1008 (Div. 1, Div. 2) Editorial | |
| 142 | Online Palindrome | brute force constructive algorithms interactive | Statement | F | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 11324 | 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 | |
| 8586 | 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 | |
| 3175 | 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 | |
| 104 | Inter Active (Hard Version) | binary search bitmasks constructive algorithms graphs implementation interactive math probabilities | Statement | G2 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2750.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 99 | Inter Active (Easy Version) | binary search constructive algorithms interactive interactive | Statement | G1 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2750.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 1655 | Interactive RBS (Hard Version) | binary search bitmasks constructive algorithms dp interactive | Statement | C3 | Codeforces Round 1040 (Div. 1) {2129} | PROGRAMMING | 750.0 | Codeforces Round 1040 (Div. 1, Div. 2) Editorial | |
| 3835 | Interactive RBS (Easy Version) | binary search bitmasks constructive algorithms interactive | Statement | C1 | Codeforces Round 1040 (Div. 1) {2129} | PROGRAMMING | 750.0 | Codeforces Round 1040 (Div. 1, Div. 2) Editorial | |
| 2485 | Interactive RBS (Medium Version) | binary search bitmasks constructive algorithms interactive | Statement | C2 | Codeforces Round 1040 (Div. 1) {2129} | PROGRAMMING | 750.0 | Codeforces Round 1040 (Div. 1, Div. 2) Editorial | |
| 2379 | Power Boxes | constructive algorithms dp interactive | Statement | E | Codeforces Round 1045 (Div. 2) {2134} | PROGRAMMING | 2250.0 | 145832 | |
| 986 | From the Unknown (Hard Version) | binary search brute force constructive algorithms interactive math | Statement | D2 | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 1250.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 7299 | For the Champion | constructive algorithms interactive math | Statement | B | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 1000.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 2409 | From the Unknown (Easy Version) | constructive algorithms interactive math | Statement | D1 | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 1250.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 2757 | Monotone Subsequence | brute force constructive algorithms dp graphs interactive math | Statement | E | Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) {2152} | PROGRAMMING | 3000.0 | Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) Editorial | |
| 5337 | Find the Last Number | bitmasks constructive algorithms interactive math | Statement | D | Codeforces Round 1061 (Div. 2) {2156} | PROGRAMMING | 2000.0 | Codeforces Round 1061 (Div. 2) Editorial | |
| 402 | Isaac's Queries | brute force constructive algorithms dfs and similar divide and conquer greedy interactive math probabilities | Statement | G | Codeforces Round 1066 (Div. 1 + Div. 2) {2157} | PROGRAMMING | 3000.0 | Codeforces Round 1066 (Div. 1 + Div. 2) Editorial | |
| 8086 | MAD Interactive Problem | constructive algorithms implementation interactive | Statement | A | Codeforces Round 1058 (Div. 1) {2159} | PROGRAMMING | 750.0 | Codeforces Round 1058 Editorial | |
| 1541 | Locate | binary search constructive algorithms greedy interactive | Statement | B | Testing Round 20 (Unrated, Communication Problems) {2168} | PROGRAMMING | Testing Round 20 Editorial (officially unofficial) | ||
| 867 | Intercepting Butterflies | bitmasks constructive algorithms graphs interactive | Statement | C | Testing Round 20 (Unrated, Communication Problems) {2168} | PROGRAMMING | Testing Round 20 Editorial (officially unofficial) | ||
| 5006 | Encode and Decode (Easy Version) | constructive algorithms interactive | Statement | A1 | Testing Round 20 (Unrated, Communication Problems) {2168} | PROGRAMMING | Testing Round 20 Editorial (officially unofficial) | ||
| 49 | Bowser's Castle (Easy Version) | binary search constructive algorithms divide and conquer greedy interactive trees | Statement | H1 | Codeforces Round 1085 (Div. 1 + Div. 2) {2207} | PROGRAMMING | 3250.0 | Codeforces Round 1085 (Div. 1 + Div. 2) Editorial | |
| 37 | Bowser's Castle (Medium Version) | constructive algorithms divide and conquer interactive trees two pointers | Statement | H2 | Codeforces Round 1085 (Div. 1 + Div. 2) {2207} | PROGRAMMING | 1000.0 | Codeforces Round 1085 (Div. 1 + Div. 2) Editorial | |
| 53 | Bowser's Castle (Hard Version) | constructive algorithms divide and conquer interactive trees two pointers | Statement | H3 | Codeforces Round 1085 (Div. 1 + Div. 2) {2207} | PROGRAMMING | 1500.0 | Codeforces Round 1085 (Div. 1 + Div. 2) Editorial | |
| 10175 | Find the Zero | constructive algorithms interactive | Statement | C | Codeforces Round 1087 (Div. 2) {2209} | PROGRAMMING | 1500.0 | Codeforces Round 1087 (Div. 2) Editorial | |
| 297 | 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 | |
| 477 | Oriented Journey | bitmasks communication constructive algorithms graphs hashing interactive trees | Statement | C | Codeforces Round 1092 (Unrated, Div. 1, Based on THUPC 2026 — Finals) {2215} | PROGRAMMING | 1750.0 | ||
| 2563 | Unique Values (Hard version) | binary search constructive algorithms divide and conquer interactive math | Statement | B2 | Codeforces Round 1093 (Div. 1) {2219} | PROGRAMMING | 500.0 |