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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 7931 | Fortune Telling | implementation number theory | Statement | B | Codeforces Beta Round 55 (Div. 2) {59} | PROGRAMMING | Round 55 (DIV 2) | 1200 | |
| 2011 | Harry Potter and Three Spells | implementation math | Statement | A | Codeforces Beta Round 60 {65} | PROGRAMMING | Codeforces Beta Round #60: tutorial | 1800 | |
| 5353 | Irrational problem | implementation number theory | Statement | A | Codeforces Beta Round 62 {68} | PROGRAMMING | Разбор задачи D. CF62 | 1100 | |
| 3973 | Prime Permutation | implementation number theory strings | Statement | A | Codeforces Beta Round 92 (Div. 1 Only) {123} | PROGRAMMING | Codeforces Beta Round #92 - Analysis | 1600 | |
| 1481 | ucyhf | *special brute force implementation number theory | Statement | F | April Fools Day Contest {171} | PROGRAMMING | April Fools Day Contest: editorial | 1700 | |
| 3144 | Pseudorandom Sequence Period | *special implementation number theory | Statement | B | Croc Champ 2012 - Qualification Round {172} | PROGRAMMING | 1800 | ||
| 30225 | 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 | |
| 364 | Tractor College | implementation math number theory ternary search | Statement | E | Codeforces Round 126 (Div. 2) {200} | PROGRAMMING | Editorial of Codeforces Round #126 (Div. 2) | 2200 | |
| 2912 | Reducing Fractions | implementation math number theory sortings | Statement | C | Codeforces Round 137 (Div. 2) {222} | PROGRAMMING | Разбор задач Codeforces Round #137 (Div. 2) | 2000 | |
| 1013 | Anniversary | data structures implementation math matrices number theory | Statement | C | Codeforces Round 140 (Div. 1) {226} | PROGRAMMING | Codeforces Round #140 Editorial | 2100 | |
| 95160 | T-primes | binary search implementation math number theory | Statement | B | Codeforces Round 142 (Div. 2) {230} | PROGRAMMING | Codeforces Round #142 Problem Analysis | 1300 | |
| 884 | Number Challenge | combinatorics dp implementation math number theory | Statement | E | Codeforces Round 146 (Div. 1) {235} | PROGRAMMING | Codeforces Round #146 Tutorial | 2600 | |
| 16874 | Easy Number Challenge | implementation number theory | Statement | B | Codeforces Round 146 (Div. 2) {236} | PROGRAMMING | Codeforces Round #146 Tutorial | 1300 | |
| 7324 | Cows and Primitive Roots | implementation math number theory | Statement | A | Codeforces Round 174 (Div. 2) {284} | PROGRAMMING | Editorial for Codeforces #174 | 1400 | |
| 378 | Shaass and Painter Robot | brute force implementation number theory | Statement | D | Codeforces Round 178 (Div. 2) {294} | PROGRAMMING | Codeforces Round #178 Editorial | 2700 | |
| 64806 | Ilya and Bank Account | implementation number theory | Statement | A | Codeforces Round 186 (Div. 2) {313} | PROGRAMMING | Tutorial | 900 | |
| 2654 | Vasily the Bear and Sequence | brute force greedy implementation number theory | Statement | C | Codeforces Round 195 (Div. 2) {336} | PROGRAMMING | Tutorial Codeforces Round #195 (Div. 2) | 1800 | |
| 5251 | Find Maximum | implementation math number theory | Statement | C | Codeforces Round 205 (Div. 2) {353} | PROGRAMMING | 9145 | 1600 | |
| 10545 | Bear and Prime Numbers | binary search brute force data structures dp implementation math number theory | Statement | C | Codeforces Round 226 (Div. 2) {385} | PROGRAMMING | Codeforces Round #226 (Div. 2) — Editorial | 1800 | |
| 1089 | Population Size | greedy implementation math | Statement | D | Codeforces Round 241 (Div. 2) {416} | PROGRAMMING | Codeforces Round #241 — editorial | 2300 | |
| 4167 | 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 | |
| 1633 | Divisors | brute force dfs and similar implementation number theory | Statement | E | Codeforces Round 256 (Div. 2) {448} | PROGRAMMING | Codeforces Round #256 — Разбор | 2500 | |
| 13359 | Little Dima and Equation | brute force implementation math number theory | Statement | B | Codeforces Round 262 (Div. 2) {460} | PROGRAMMING | 13465 | 1500 | |
| 24841 | Counterexample | brute force implementation math number theory | Statement | A | Codeforces Round 275 (Div. 2) {483} | PROGRAMMING | Codeforces Round #275 Editorial | 1100 | |
| 44689 | Lecture | implementation strings | Statement | B | Codeforces Round 284 (Div. 2) {499} | PROGRAMMING | 15353 | 1000 | |
| 20690 | A and B and Team Training | greedy implementation math number theory | Statement | C | Codeforces Round 294 (Div. 2) {519} | PROGRAMMING | Editorial | 1300 | |
| 2097 | GukiZ and Binary Operations | combinatorics implementation math matrices number theory | Statement | D | Codeforces Round 307 (Div. 2) {551} | PROGRAMMING | Tutorial | 2400 | |
| 5397 | Primes or Palindromes? | brute force implementation math number theory | Statement | A | Codeforces Round 315 (Div. 1) {568} | PROGRAMMING | Codeforces Round #315 Editorial | 1700 | |
| 18154 | Bear and Poker | implementation math number theory | Statement | A | Codeforces Round 318 [RussianCodeCup Thanks-Round] (Div. 1) {573} | PROGRAMMING | Codeforces Round #318 [RussianCodeCup Thanks-Round] Editorial | 1400 | |
| 45166 | Multiplication Table | implementation number theory | Statement | A | Codeforces Round 319 (Div. 2) {577} | PROGRAMMING | Editorial Codeforces Round #319 | 1100 | |
| 3476 | Sum of Remainders | implementation math number theory | Statement | E | Educational Codeforces Round 5 {616} | PROGRAMMING | Editorial of Educational Codeforces Round 5 | 2200 | |
| 1570 | Little Artem and Random Variable | dp implementation math probabilities | Statement | D | VK Cup 2016 - Round 2 {641} | PROGRAMMING | VK Cup 2016 — Раунд 2 (editorial) | 2300 | |
| 10251 | Co-prime Array | greedy implementation math number theory | Statement | A | Educational Codeforces Round 11 {660} | PROGRAMMING | Editorial of Educational Codeforces Round 11 | 1300 | |
| 10991 | Joty and Chocolate | implementation math number theory | Statement | C | Educational Codeforces Round 13 {678} | PROGRAMMING | Editorial | 1600 | |
| 524 | Black Widow | dp graphs implementation math | Statement | C | Codeforces Round 366 (Div. 1) {704} | PROGRAMMING | Tutorial | 2800 | |
| 605 | Cyclic Cipher | chinese remainder theorem data structures implementation number theory two pointers | Statement | F | Intel Code Challenge Elimination Round (Div. 1 + Div. 2, combined) {722} | PROGRAMMING | Tutorial | 2800 | |
| 2264 | Ray Tracing | greedy hashing implementation math number theory sortings | Statement | C | Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} | PROGRAMMING | Tutorial | 1800 | |
| 3137 | Video Cards | brute force data structures implementation math number theory | Statement | F | Codeforces Round 376 (Div. 2) {731} | PROGRAMMING | 47840 | 1900 | |
| 51720 | Arpa’s hard exam and Mehrdad’s naive cheat | implementation math number theory | Statement | A | Codeforces Round 383 (Div. 2) {742} | PROGRAMMING | Test data | 1000 | |
| 56864 | Bachgold Problem | greedy implementation math number theory | Statement | A | Codeforces Round 388 (Div. 2) {749} | PROGRAMMING | Tutorial | 700 | |
| 10692 | Blown Garland | brute force implementation number theory | Statement | B | Codeforces Round 392 (Div. 2) {758} | PROGRAMMING | Codeforces Round #392 (Div. 2) Editorial | 1200 | |
| 776 | Timofey and remoduling | brute force implementation math number theory | Statement | C | Codeforces Round 395 (Div. 1) {763} | PROGRAMMING | Codeforces Round #395 [Editorial] | 2500 | |
| 19773 | k-Factorization | implementation math number theory | Statement | A | Educational Codeforces Round 19 {797} | PROGRAMMING | 51588 | 1100 | |
| 6807 | Treasure Hunt | implementation math number theory | Statement | A | Educational Codeforces Round 23 {817} | PROGRAMMING | 52638 | 1200 | |
| 36677 | I'm bored with life | implementation math number theory | Statement | A | Codeforces Round 422 (Div. 2) {822} | PROGRAMMING | Codeforces Round #422 (Div. 2) Editorial | 800 | |
| 1306 | Bamboo Partition | brute force data structures implementation math number theory sortings two pointers | Statement | C | Codeforces Round 424 (Div. 1, rated, based on VK Cup Finals) {830} | PROGRAMMING | Codeforces Round #424 Editorial | 2500 | |
| 2057 | Vasya's Function | binary search implementation math | Statement | E | Educational Codeforces Round 26 {837} | PROGRAMMING | 53662 | 2200 | |
| 2127 | Arpa and a list of numbers | implementation number theory | Statement | B | Codeforces Round 432 (Div. 1, based on IndiaHacks Final Round 2017) {850} | PROGRAMMING | Codeforces Round #432 editorial | 2000 | |
| 10308 | Divisiblity of Differences | implementation math number theory | Statement | B | Codeforces Round 441 (Div. 2, by Moscow Team Olympiad) {876} | PROGRAMMING | Codeforces Round #441. Editorial. | 1300 | |
| 10598 | Proper Nutrition | brute force implementation number theory | Statement | B | Codeforces Round 451 (Div. 2) {898} | PROGRAMMING | Codeforces Round #451 (Div.2) Editorial | 1300 | |
| 31548 | Perfect Number | binary search brute force dp implementation number theory | Statement | B | Codeforces Round 460 (Div. 2) {919} | PROGRAMMING | Codeforces Round #460 (Div. 2) Editorial | 1100 | |
| 10690 | Multiplicity | data structures dp implementation math number theory | Statement | C | Codeforces Round 523 (Div. 2) {1061} | PROGRAMMING | Tutorial (en) | 1700 | |
| 14555 | Divisor Subtraction | implementation math number theory | Statement | B | Educational Codeforces Round 54 (Rated for Div. 2) {1076} | PROGRAMMING | E | 1200 | |
| 273 | Fedya the Potter | binary search implementation math number theory | Statement | E | Codeforces Round 530 (Div. 1) {1098} | PROGRAMMING | 64331 | 3400 | |
| 3900 | Compression | dp implementation math number theory | Statement | D | Educational Codeforces Round 59 (Rated for Div. 2) {1107} | PROGRAMMING | Educational Codeforces Round 59 Editorial | 1800 | |
| 7823 | Trailing Loves (or L'oeufs?) | brute force implementation math number theory | Statement | C | Codeforces Round 538 (Div. 2) {1114} | PROGRAMMING | Codeforces Round #538 (Div. 2) Editorial | 1700 | |
| 1162 | Graph Traveler | brute force data structures dfs and similar dp graphs implementation math number theory | Statement | F | Codeforces Round 578 (Div. 2) {1200} | PROGRAMMING | Codeforces Round #578 (Div. 2) Editorial | 2500 | |
| 8510 | Koala and Lights | implementation math number theory | Statement | B | Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} | PROGRAMMING | 69791 | 1300 | |
| 18314 | Adding Powers | bitmasks greedy implementation math number theory ternary search | Statement | C | Educational Codeforces Round 83 (Rated for Div. 2) {1312} | PROGRAMMING | 74640 | ||
| 27280 | Yet Another Tetris Problem | implementation number theory | Statement | A | Codeforces Round 627 (Div. 3) {1324} | PROGRAMMING | Codeforces Round #627 (Div. 3) Editorial | ||
| 19852 | Exercising Walk | greedy implementation math | Statement | A | Codeforces Round 630 (Div. 2) {1332} | PROGRAMMING | 500.0 | Codeforces Round #630 Editorial | 1200 |
| 4566 | Kate and imperfection | greedy implementation math number theory sortings two pointers | Statement | F | Codeforces Round 632 (Div. 2) {1333} | PROGRAMMING | 2500.0 | Codeforces Round #632 (Div. 2) editorial | |
| 64005 | Maximum GCD | brute force greedy implementation number theory | Statement | A | Codeforces Round 651 (Div. 2) {1370} | PROGRAMMING | 500.0 | Editorial — Codeforces Round #651 | |
| 5523 | Asterism (Easy Version) | brute force combinatorics implementation math number theory sortings | Statement | E1 | Codeforces Round 654 (Div. 2) {1371} | PROGRAMMING | 1500.0 | Codeforces Round #654 (Div. 2) Editorial | |
| 12325 | Acacius and String | brute force implementation strings | Statement | A | Codeforces Round 657 (Div. 2) {1379} | PROGRAMMING | 500.0 | Codeforces Round #657 Editorial | 1500 |
| 3494 | Decryption | bitmasks constructive algorithms implementation math number theory | Statement | E | Codeforces Round 671 (Div. 2) {1419} | PROGRAMMING | 2250.0 | Codeforces Round #671 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 | |
| 20521 | Scenes From a Memory | brute force implementation math number theory | Statement | B | Codeforces Round 741 (Div. 2) {1562} | PROGRAMMING | 1000.0 | Editorial of Codeforces Round 741 (Div. 2) | |
| 5337 | Array Stabilization (AND version) | binary search brute force graphs greedy implementation math number theory shortest paths | Statement | F | Codeforces Round 744 (Div. 3) {1579} | PROGRAMMING | Codeforces Round #744 (Div. 3) Editorial | ||
| 1181 | Array Equalizer | binary search implementation math number theory sortings | Statement | E | Codeforces Round 754 (Div. 2) {1605} | PROGRAMMING | 2500.0 | tutorial | 2400 |
| 10435 | Complex Market Analysis | binary search dp implementation number theory schedules two pointers | Statement | C | Deltix Round, Autumn 2021 (open for everyone, rated, Div. 1 + Div. 2) {1609} | PROGRAMMING | 1500.0 | Deltix Round, Autumn 2021. Editorial | 1400 |
| 18862 | Divide and Multiply | greedy implementation math number theory | Statement | A | Deltix Round, Autumn 2021 (open for everyone, rated, Div. 1 + Div. 2) {1609} | PROGRAMMING | 500.0 | Deltix Round, Autumn 2021. Editorial | 900 |
| 1008 | Christmas Chocolates | dfs and similar dp games graphs implementation math number theory shortest paths trees | Statement | E | Codeforces Round 761 (Div. 2) {1617} | PROGRAMMING | 3000.0 | Editorial for Codeforces Round #761 (Div. 2) | |
| 3057 | Potion Brewing Class | dfs and similar implementation math number theory trees | Statement | D | Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} | PROGRAMMING | 2000.0 | Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) | 2100 |
| 3622 | Lost Arithmetic Progression | combinatorics implementation math number theory | Statement | D | Codeforces Round 785 (Div. 2) {1673} | PROGRAMMING | 2000.0 | Codeforces Round #785 (Div. 2) Editorial | |
| 3449 | Fibonacci Strings | brute force data structures greedy implementation math number theory | Statement | B | Codeforces Round 814 (Div. 1) {1718} | PROGRAMMING | 1250.0 | Codeforces Round #814 (Div. 1, Div. 2) Editorial | |
| 17493 | Bestie | brute force constructive algorithms implementation math number theory | Statement | A | Codeforces Round 830 (Div. 2) {1732} | PROGRAMMING | 750.0 | 108327 | 1000 |
| 18595 | 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 | |
| 964 | Serval and Music Game | brute force combinatorics implementation math number theory | Statement | E | Codeforces Round 853 (Div. 2) {1789} | PROGRAMMING | 2000.0 | Codeforces Round #853 (Div. 2) Editorial | |
| 2761 | MEX of LCM | binary search brute force data structures implementation math number theory two pointers | Statement | E | Codeforces Round 879 (Div. 2) {1834} | PROGRAMMING | 2500.0 | Codeforces Round #879 Editorial | |
| 24477 | We Were Both Children | brute force implementation math number theory | Statement | F | Codeforces Round 886 (Div. 4) {1850} | PROGRAMMING | Codeforces Round #886 (Div. 4) Editorial | ||
| 12999 | The Walkway | brute force greedy implementation math number theory | Statement | B | Codeforces Round 893 (Div. 2) {1858} | PROGRAMMING | 1250.0 | Codeforces Round #893 (Div. 2) Editorial | 1500 |
| 4546 | Suspicious logarithms | binary search brute force implementation math number theory | Statement | D | Codeforces Round 907 (Div. 2) {1891} | PROGRAMMING | 1500.0 | ||
| 33081 | 250 Thousand Tons of TNT | brute force implementation number theory | Statement | B | Codeforces Round 909 (Div. 3) {1899} | PROGRAMMING | Разбор Codeforces Round 909 (Div. 3) | ||
| 28259 | 2023 | constructive algorithms implementation math number theory | Statement | A | Good Bye 2023 {1916} | PROGRAMMING | 250.0 | ||
| 14797 | Vlad and an Odd Ordering | binary search bitmasks data structures dp implementation math number theory | Statement | E | Codeforces Round 928 (Div. 4) {1926} | PROGRAMMING | 126132 | ||
| 2088 | 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 | |
| 10151 | Final Countdown | implementation math number theory | Statement | E | Codeforces Round 927 (Div. 3) {1932} | PROGRAMMING | 126196 | ||
| 36194 | Turtle Math: Fast Three Task | implementation number theory | Statement | B | Codeforces Round 929 (Div. 3) {1933} | PROGRAMMING | Codeforces Round 929 (Div. 3) Editorial | ||
| 17378 | Nearly Shortest Repeating Substring | brute force implementation number theory strings | Statement | E | Codeforces Round 937 (Div. 4) {1950} | PROGRAMMING | Codeforces Round 937 (Div. 4) Editorial | ||
| 26438 | Product of Binary Decimals | dp implementation number theory | Statement | D | Codeforces Round 937 (Div. 4) {1950} | PROGRAMMING | Codeforces Round 937 (Div. 4) Editorial | ||
| 2955 | Chain Reaction | data structures dsu greedy implementation math number theory | Statement | E | Educational Codeforces Round 164 (Rated for Div. 2) {1954} | PROGRAMMING | Educational Codeforces Round 164 Editorial | ||
| 319 | Maximum GCD Sum Queries | bitmasks brute force dp implementation number theory | Statement | F | Codeforces Round 945 (Div. 2) {1973} | PROGRAMMING | 3000.0 | Editorial for Codeforces Round #945 (Div. 2) | 3100 |
| 17321 | GCD-sequence | greedy implementation math math number theory number theory | Statement | D | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 9709 | Beauty of the mountains | brute force data structures implementation math number theory | Statement | D | Codeforces Round 955 (Div. 2, with prizes from NEAR!) {1982} | PROGRAMMING | 1750.0 | 130839 | |
| 19727 | Collatz Conjecture | brute force implementation math number theory | Statement | B | Codeforces Round 955 (Div. 2, with prizes from NEAR!) {1982} | PROGRAMMING | 1000.0 | 130839 | |
| 10254 | 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 | |
| 24642 | Circuit | greedy implementation math number theory | Statement | A | Codeforces Round 983 (Div. 2) {2032} | PROGRAMMING | 500.0 | Codeforces Round 983 (Div. 2) Editorial | |
| 22814 | Kevin and Combination Lock | brute force implementation math number theory | Statement | A | Codeforces Global Round 28 {2048} | PROGRAMMING | 250.0 | Tutorial | |
| 2481 | Red Light, Green Light (Hard version) | binary search dfs and similar dp dsu graphs implementation number theory | Statement | D2 | Codeforces Round 1030 (Div. 2) {2118} | PROGRAMMING | 1000.0 | Codeforces Round 1030 (Div. 2) Editorial | |
| 749 | Attraction Theory | combinatorics dp implementation math | Statement | D | Codeforces Round 1053 (Div. 1) {2150} | PROGRAMMING | 2500.0 | Editorial of Codeforces Round 1053 (Div. 1, Div. 2) | |
| 13422 | No Cost Too Great (Easy Version) | greedy implementation math number theory | Statement | C1 | Codeforces Round 1060 (Div. 2) {2154} | PROGRAMMING | 1250.0 | Codeforces Round 1060 (Div. 2) Editorial | |
| 8453 | Removal of a Sequence (Easy Version) | binary search bitmasks geometry implementation math number theory | Statement | D1 | Educational Codeforces Round 184 (Rated for Div. 2) {2169} | PROGRAMMING | Educational Codeforces Round 184 Editorial | ||
| 2251 | 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 | ||
| 766 | RReeppeettiittiioonn | binary search brute force implementation math number theory | Statement | B | Codeforces Round 1092 (Unrated, Div. 1, Based on THUPC 2026 — Finals) {2215} | PROGRAMMING | 1250.0 |