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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 16205 | Bear and Prime 100 | constructive algorithms interactive math | Statement | A | Codeforces Round 356 (Div. 1) {679} | PROGRAMMING | Codeforces Round #356 — Editorial | 1400 | |
| 9341 | 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 | |
| 2675 | Divisors | interactive math number theory | Statement | D | Lyft Level 5 Challenge 2018 - Elimination Round {1033} | PROGRAMMING | The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial | 2000 | |
| 257 | New Year and the Factorisation Collaboration | interactive math number theory | Statement | G | Good Bye 2018 {1091} | PROGRAMMING | Editorial | 3100 | |
| 1675 | 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 | |
| 1718 | Guess the Root | brute force interactive math | Statement | E | Educational Codeforces Round 63 (Rated for Div. 2) {1155} | PROGRAMMING | 66687 | 2200 | |
| 233 | Strange device | binary search interactive math trees | Statement | E | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 3300 | |
| 17781 | Lost Numbers | brute force divide and conquer interactive math | Statement | B | Educational Codeforces Round 65 (Rated for Div. 2) {1167} | PROGRAMMING | 67058 | 1400 | |
| 6826 | XOR Guessing | bitmasks interactive math | Statement | E | Educational Codeforces Round 71 (Rated for Div. 2) {1207} | PROGRAMMING | Educational Codeforces Round 71 Editorial | 1800 | |
| 1832 | Point Ordering | constructive algorithms geometry interactive math | Statement | C | Codeforces Round 601 (Div. 1) {1254} | PROGRAMMING | Codeforces Round #601 Editorial | 2300 | |
| 5017 | Strange Device | constructive algorithms interactive math sortings | Statement | D | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 1900 | |
| 1633 | Madhouse (Easy version) | brute force constructive algorithms interactive math | Statement | C1 | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 2400 | |
| 784 | Madhouse (Hard version) | brute force constructive algorithms hashing interactive math | Statement | C2 | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 2900 | |
| 482 | 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 |
| 278 | So Mean | interactive math | Statement | E | Codeforces Round 618 (Div. 1) {1299} | PROGRAMMING | 2250.0 | Codeforces Round #618 Editorial | 3400 |
| 4485 | Guess The Maximums | binary search divide and conquer implementation interactive math | Statement | D | Codeforces Round 646 (Div. 2) {1363} | PROGRAMMING | 2000.0 | 78202 | 2100 |
| 1568 | Secure Password | bitmasks combinatorics constructive algorithms interactive math | Statement | G | Codeforces Round 648 (Div. 2) {1365} | PROGRAMMING | 3000.0 | Editorial — Codeforces Round #648 | 2800 |
| 1135 | Lamps on a Circle | games greedy implementation interactive math | Statement | F | Codeforces Global Round 8 {1368} | PROGRAMMING | 3000.0 | Codeforces Global Round 8: editorial | |
| 2598 | Integer Game | brute force constructive algorithms games interactive math | Statement | F | Codeforces Global Round 9 {1375} | PROGRAMMING | 2000.0 | 79731 | |
| 3967 | Omkar and Duck | bitmasks constructive algorithms interactive math | Statement | E | Codeforces Global Round 10 {1392} | PROGRAMMING | 2000.0 | Codeforces Global Round 10 — Editorial | |
| 1324 | 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 | |
| 15546 | Chocolate Bunny | constructive algorithms interactive math two pointers | Statement | C | Codeforces Round 669 (Div. 2) {1407} | PROGRAMMING | 1500.0 | Codeforces Round #669 Editorial | |
| 5632 | Bitwise Queries (Easy Version) | bitmasks constructive algorithms interactive math | Statement | E1 | Codeforces Round 685 (Div. 2) {1451} | PROGRAMMING | 1500.0 | Editorial — Codeforces Round #685 | |
| 4012 | Bitwise Queries (Hard Version) | bitmasks constructive algorithms interactive math | Statement | E2 | Codeforces Round 685 (Div. 2) {1451} | PROGRAMMING | 1000.0 | Editorial — Codeforces Round #685 | |
| 606 | Is It Rated? | greedy interactive math probabilities | Statement | I | 2020-2021 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1510} | PROGRAMMING | nerc-2020-offline-tutorial.pdf | ||
| 8077 | 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 | |
| 2215 | 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 | |
| 814 | AquaMoon and Wrong Coordinate | constructive algorithms interactive math | Statement | D | Codeforces Round 732 (Div. 1) {1545} | PROGRAMMING | 2250.0 | Codeforces Round #732 Editorial | 3000 |
| 472 | Guess the Perimeter | binary search interactive number theory | Statement | H | Codeforces Global Round 15 {1552} | PROGRAMMING | 2750.0 | Editorial of Global Round 15 | |
| 9106 | 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 |
| 484 | Tubular Bells | interactive math number theory probabilities | Statement | F | Codeforces Round 741 (Div. 2) {1562} | PROGRAMMING | 3500.0 | Editorial of Codeforces Round 741 (Div. 2) | |
| 187 | Xor-quiz | constructive algorithms dp interactive math number theory | Statement | H | Codeforces Global Round 16 {1566} | PROGRAMMING | 3750.0 | Codeforces Global Round 16 Editorial | |
| 4065 | Guess the Permutation | binary search combinatorics interactive math | Statement | D | Technocup 2022 - Elimination Round 2 {1584} | PROGRAMMING | 1500.0 | Editorial for Technocup 2022 — Elimination Round 2 and Codeforces Round #755 (Div. 1, Div. 2) | 2000 |
| 2682 | Hemose in ICPC ? | binary search dfs and similar divide and conquer interactive math number theory trees | Statement | D | Codeforces Round 746 (Div. 2) {1592} | PROGRAMMING | 2000.0 | 95583 | |
| 1331 | Hidden Fortress | interactive math | Statement | H | Bubble Cup 14 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred, Div. 1) {1599} | PROGRAMMING | BubbleCup2021.pdf | ||
| 7585 | Hidden Permutations | dfs and similar interactive math | Statement | C | Hello 2022 {1621} | PROGRAMMING | 1500.0 | ||
| 3722 | Grid Xor | constructive algorithms greedy implementation interactive math | Statement | C | Codeforces Round 767 (Div. 1) {1628} | PROGRAMMING | 1250.0 | 99276 | |
| 4830 | 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 | |
| 1806 | Interactive Treasure Hunt | brute force interactive math | Statement | I | 2021-2022 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1666} | PROGRAMMING | Tutorial (PDF) | ||
| 1006 | 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 | |
| 731 | 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 | |
| 611 | Crop Squares | constructive algorithms geometry interactive math | Statement | F | Codeforces Round 816 (Div. 2) {1715} | PROGRAMMING | 3000.0 | Codeforces Round #816 (Div. 2) editorial | |
| 1853 | 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 | |
| 3722 | 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 |
| 387 | Roads in E City | interactive math probabilities trees | Statement | E | Codeforces Round 866 (Div. 1) {1819} | PROGRAMMING | 2750.0 | Codeforces Round #866 (Div.1, Div.2, based on Lipetsk Team Olympiad) Editorial | |
| 492 | Fading into Fog | geometry interactive math probabilities | Statement | F | Codeforces Round 870 (Div. 2) {1826} | PROGRAMMING | 3000.0 | Codeforces Round #870 (Div. 2) Editorial | 2800 |
| 2886 | 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 | ||
| 1231 | 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 | ||
| 4452 | Salyg1n and Array (simple version) | constructive algorithms interactive math | Statement | E1 | Codeforces Round 897 (Div. 2) {1867} | PROGRAMMING | 2000.0 | ||
| 3851 | Salyg1n and Array (hard version) | constructive algorithms interactive math | Statement | E2 | Codeforces Round 897 (Div. 2) {1867} | PROGRAMMING | 1000.0 | ||
| 1636 | 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 | |
| 2640 | 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 | |
| 187 | Tree Diameter | interactive trees | Statement | H | Hello 2024 {1919} | PROGRAMMING | 5000.0 | 3500 | |
| 8317 | Find a Mine | constructive algorithms geometry greedy interactive math | Statement | C | Codeforces Round 931 (Div. 2) {1934} | PROGRAMMING | 1500.0 | Tutorial | |
| 8818 | 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 | |
| 2355 | Cat, Fox and Maximum Array Split | brute force interactive math | Statement | D | Codeforces Round 945 (Div. 2) {1973} | PROGRAMMING | 2000.0 | Editorial for Codeforces Round #945 (Div. 2) | 2400 |
| 783 | Fortnite | interactive math | Statement | H | Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} | PROGRAMMING | 3750.0 | Video Tutorial | |
| 15238 | Ruler (easy version) | binary search interactive ternary search | Statement | G1 | Codeforces Round 964 (Div. 4) {1999} | PROGRAMMING | Video Tutorial | ||
| 11739 | Ruler (hard version) | binary search interactive ternary search | Statement | G2 | Codeforces Round 964 (Div. 4) {1999} | PROGRAMMING | Video Tutorial | ||
| 7697 | Kachina's Favorite Binary String | greedy interactive two pointers | Statement | E | Codeforces Round 988 (Div. 3) {2037} | PROGRAMMING | Video Tutorial | ||
| 6943 | Empty Triangle | geometry interactive probabilities | Statement | E | Codeforces Round 1009 (Div. 3) {2074} | PROGRAMMING | Codeforces Round 1009 (Div. 3) — Editorial | ||
| 3824 | 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 | |
| 2495 | Needle in a Numstack | binary search brute force interactive math | Statement | D | Codeforces Round 1022 (Div. 2) {2108} | PROGRAMMING | 2250.0 | Codeforces Round 1022 Editorial | |
| 11976 | 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 | |
| 9063 | 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 | |
| 3472 | 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 | |
| 172 | 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 | |
| 1495 | 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 | |
| 9479 | 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 | |
| 4329 | 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 | |
| 896 | Hidden Single (Version 2) | divide and conquer interactive math probabilities | Statement | E2 | Codeforces Round 1053 (Div. 1) {2150} | PROGRAMMING | 1750.0 | Editorial of Codeforces Round 1053 (Div. 1, Div. 2) | |
| 2922 | Hidden Single (Version 1) | divide and conquer interactive math probabilities sortings | Statement | E1 | Codeforces Round 1053 (Div. 1) {2150} | PROGRAMMING | 2000.0 | Editorial of Codeforces Round 1053 (Div. 1, Div. 2) | |
| 4809 | 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 | |
| 6332 | Batteries | interactive math | Statement | D | Codeforces Round 1056 (Div. 2) {2155} | PROGRAMMING | 2000.0 | Codeforces Round 1056 (Div. 2) Editorial | |
| 5627 | 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 | |
| 991 | 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 | |
| 3613 | Encode and Decode (Hard Version) | bitmasks interactive math | Statement | A2 | Testing Round 20 (Unrated, Communication Problems) {2168} | PROGRAMMING | Testing Round 20 Editorial (officially unofficial) | ||
| 1666 | Shiro's Mirror Duel | interactive probabilities | Statement | E | Codeforces Round 1068 (Div. 2) {2173} | PROGRAMMING | 2250.0 | ||
| 120 | Game of Scientists (Version 2) | brute force chinese remainder theorem interactive math | Statement | E2 | Codeforces Round 1069 (Div. 1) {2174} | PROGRAMMING | 1750.0 | Codeforces Round 1069 Editorial | |
| 167 | Game of Scientists (Version 1) | chinese remainder theorem interactive math | Statement | E1 | Codeforces Round 1069 (Div. 1) {2174} | PROGRAMMING | 1750.0 | Codeforces Round 1069 Editorial | |
| 1333 | Blackslex and Penguin Migration | brute force interactive math | Statement | G | Codeforces Round 1071 (Div. 3) {2179} | PROGRAMMING | Codeforces Round 1071 (Div. 3) Editorial | ||
| 178 | Cacti Classification | binary search interactive math | Statement | C | 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} | PROGRAMMING | Tutorial | ||
| 393 | 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 | |
| 3936 | Unique Values (Hard version) | binary search constructive algorithms divide and conquer interactive math | Statement | B2 | Codeforces Round 1093 (Div. 1) {2219} | PROGRAMMING | 500.0 | Codeforces Round 1093 (Div. 1, Div. 2) Editorial | |
| 455 | Send GCDs | communication interactive math | Statement | G | Order Capital Round 2 (Codeforces Round 1104, Div. 1 + Div. 2) {2237} | PROGRAMMING | 2750.0 | Order Capital Round 2 (Codeforces Round 1104, Div. 1 + Div. 2) Editorial | |
| 696 | lce4113 and Security Game | bitmasks interactive probabilities | Statement | E | Codeforces Round 1108 (Div. 2) {2246} | PROGRAMMING | 2250.0 | Codeforces Round 1108 (Div. 2) Editorial | |
| 1618 | Even If the World Turns | communication greedy interactive math number theory | Statement | C | Codeforces Round 1116 (Div. 1) {2255} | PROGRAMMING | 1750.0 | 155840 |