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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 5526 | Quantity of Strings | combinatorics dfs and similar graphs math | Statement | B | Codeforces Round 107 (Div. 1) {150} | PROGRAMMING | Tutorial | 1800 | |
| 701 | Periodical Numbers | combinatorics dp number theory | Statement | E | Codeforces Round 132 (Div. 2) {215} | PROGRAMMING | Codeforces Round #132 (Div. 2) Tutorial | 2600 | |
| 2759 | Yaroslav and Two Strings | combinatorics dp | Statement | B | Codeforces Round 179 (Div. 2) {296} | PROGRAMMING | Codeforces Round #179 tutorial | 2000 | |
| 1245 | Vasily the Bear and Beautiful Strings | combinatorics math number theory | Statement | D | Codeforces Round 195 (Div. 2) {336} | PROGRAMMING | Tutorial Codeforces Round #195 (Div. 2) | 2400 | |
| 1277 | Levko and Strings | combinatorics dp | Statement | C | Codeforces Round 210 (Div. 1) {360} | PROGRAMMING | Codeforces Round #210 editorial | 2700 | |
| 38163 | Dreamoon and WiFi | bitmasks brute force combinatorics dp math probabilities | Statement | B | Codeforces Round 272 (Div. 2) {476} | PROGRAMMING | 1300 | ||
| 1038 | Mr. Kitayuta's Gift | combinatorics dp matrices strings | Statement | E | Codeforces Round 286 (Div. 1) {506} | PROGRAMMING | Editorial | 2900 | |
| 7583 | Hamming Distance Sum | combinatorics strings | Statement | B | Codeforces Round 336 (Div. 2) {608} | PROGRAMMING | Codeforces Round #336 Editorial | 1500 | |
| 961 | Codeword | combinatorics strings | Statement | C | Codeforces Round 349 (Div. 1) {666} | PROGRAMMING | Codeforces Round #349 Editorial | 2400 | |
| 7050 | Vanya and Label | bitmasks combinatorics implementation strings | Statement | C | Codeforces Round 355 (Div. 2) {677} | PROGRAMMING | Codeforces Round #355 (Div. 2) Editorial | 1500 | |
| 584 | Replace All | combinatorics dp math | Statement | G | Tinkoff Challenge - Final Round (Codeforces Round 414, rated, Div. 1 + Div. 2) {794} | PROGRAMMING | 3400 | ||
| 10303 | Minimum number of steps | combinatorics greedy implementation math | Statement | B | Codeforces Round 411 (Div. 1) {804} | PROGRAMMING | Codeforces Round #411 Editorial | 1400 | |
| 1277 | String Mark | combinatorics math strings | Statement | D | Codeforces Round 448 (Div. 2) {895} | PROGRAMMING | Codeforces Round #448(Div.2) Editorial | 2300 | |
| 874 | New Year and Entity Enumeration | bitmasks combinatorics dp math | Statement | E | Good Bye 2017 {908} | PROGRAMMING | Good Bye 2017 Editorial | 2400 | |
| 674 | Fibonacci String Subsequences | combinatorics dp matrices | Statement | F | Educational Codeforces Round 39 (Rated for Div. 2) {946} | PROGRAMMING | 58210 | 2500 | |
| 1420 | Side Transmutations | combinatorics strings | Statement | E | Educational Codeforces Round 52 (Rated for Div. 2) {1065} | PROGRAMMING | Educational Codeforces Round 52 Editorial | 2200 | |
| 11884 | Substring Removal | combinatorics math strings | Statement | B | Educational Codeforces Round 57 (Rated for Div. 2) {1096} | PROGRAMMING | Разбор Educational Codeforces Round 57 | 1400 | |
| 5505 | Print a 1337-string... | combinatorics constructive algorithms math strings | Statement | D | Educational Codeforces Round 70 (Rated for Div. 2) {1202} | PROGRAMMING | 68972 | 1900 | |
| 543 | Expected Value Again | combinatorics strings | Statement | E | Codeforces Round 580 (Div. 1) {1205} | PROGRAMMING | 69158 | 3100 | |
| 6536 | AB-string | binary search combinatorics dp strings | Statement | D | Educational Codeforces Round 74 (Rated for Div. 2) {1238} | PROGRAMMING | Educational Codeforces Round 74 Editorial | 1800 | |
| 31436 | Yet Another Broken Keyboard | combinatorics dp implementation | Statement | C | Codeforces Round 605 (Div. 3) {1272} | PROGRAMMING | Codeforces Round #605 (Div. 3) Editorial | 1100 | |
| 9970 | Ayoub's function | binary search combinatorics greedy math strings | Statement | C | Codeforces Round 619 (Div. 2) {1301} | PROGRAMMING | 1250.0 | Codeforces Round #619 (Div. 2) Editorial | 1700 |
| 32533 | K-th Beautiful String | combinatorics implementation math | Statement | B | Codeforces Round 629 (Div. 3) {1328} | PROGRAMMING | 75246 | 1300 | |
| 6399 | Number of Subsequences | combinatorics dp strings | Statement | F | Codeforces Round 674 (Div. 3) {1426} | PROGRAMMING | 83120 | 2000 | |
| 753 | String Counting | combinatorics dp math | Statement | G | Educational Codeforces Round 104 (Rated for Div. 2) {1487} | PROGRAMMING | 87873 | ||
| 74 | Build From Suffixes | *special combinatorics data structures | Statement | H | Kotlin Heroes: Episode 6 {1488} | PROGRAMMING | 88522 | ||
| 1702 | Chaotic Merge | combinatorics dp | Statement | E | Educational Codeforces Round 106 (Rated for Div. 2) {1499} | PROGRAMMING | Educational Codeforces Round 106 Editorial | ||
| 1585 | Oolimry and Suffix Array | combinatorics constructive algorithms math string suffix structures | Statement | E | Codeforces Round 723 (Div. 2) {1526} | PROGRAMMING | 2500.0 | Codeforces Round #723 (Div. 2) Editorial | |
| 7106 | AquaMoon and Chess | combinatorics math | Statement | B | Codeforces Round 732 (Div. 1) {1545} | PROGRAMMING | 1000.0 | Codeforces Round #732 Editorial | 1900 |
| 18315 | Combinatorics Homework | combinatorics greedy math | Statement | B | Educational Codeforces Round 114 (Rated for Div. 2) {1574} | PROGRAMMING | 95188 | ||
| 1214 | Subsequences Galore | bitmasks combinatorics dp math | Statement | G | Educational Codeforces Round 119 (Rated for Div. 2) {1620} | PROGRAMMING | 98061 | ||
| 4938 | Shuffle | combinatorics math two pointers | Statement | D | Educational Codeforces Round 120 (Rated for Div. 2) {1622} | PROGRAMMING | Educational Codeforces Round 120 Editorial | ||
| 3508 | Expand the Path | brute force combinatorics implementation math | Statement | E | Educational Codeforces Round 123 (Rated for Div. 2) {1644} | PROGRAMMING | 100227 | ||
| 3367 | Tyler and Strings | combinatorics data structures implementation strings | Statement | C | Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} | PROGRAMMING | 1500.0 | Codeforces Round #775 Editorial | |
| 3333 | Preorder | combinatorics divide and conquer dp dsu hashing trees | Statement | E | Educational Codeforces Round 127 (Rated for Div. 2) {1671} | PROGRAMMING | 102181 | ||
| 26671 | Infinite Replacement | combinatorics implementation strings | Statement | C | Codeforces Round 786 (Div. 3) {1674} | PROGRAMMING | 102482 | ||
| 1459 | Typical Party in Dorm | bitmasks brute force combinatorics dp strings two pointers | Statement | E | Codeforces Round 791 (Div. 2) {1679} | PROGRAMMING | 2250.0 | Codeforces Round #791 (Div. 2) Editorial | |
| 2604 | Cut Substrings | combinatorics dp hashing strings two pointers | Statement | G | Codeforces Round 820 (Div. 3) {1729} | PROGRAMMING | Codeforces Round #820 (Div. 3) Editorial | ||
| 444 | Antifibonacci Cut | bitmasks combinatorics dp math | Statement | G | Educational Codeforces Round 137 (Rated for Div. 2) {1743} | PROGRAMMING | Educational Codeforces Round 137 Editorial | 3000 | |
| 10236 | Binary Strings are Fun | combinatorics dp | Statement | C | Codeforces Round 838 (Div. 2) {1762} | PROGRAMMING | 1750.0 | Codeforces Round #838 (Div. 2) Editorial | |
| 2454 | Another Wine Tasting Event | combinatorics constructive algorithms strings | Statement | G | SWERC 2022-2023 - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1776} | PROGRAMMING | |||
| 3567 | Flexible String Revisit | combinatorics dp math probabilities | Statement | D | Codeforces Round 848 (Div. 2) {1778} | PROGRAMMING | 1750.0 | Codeforces Round #848 (Div. 2) Editorial | |
| 2339 | Hyperregular Bracket Strings | combinatorics hashing number theory sortings two pointers | Statement | C | Codeforces Round 875 (Div. 1) {1830} | PROGRAMMING | 1750.0 | Codeforces Round #875 (Div.1 + Div. 2) Editorial | |
| 3127 | Guess Game | bitmasks combinatorics constructive algorithms data structures games math probabilities strings trees | Statement | E | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) {1864} | PROGRAMMING | 2000.0 | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Editorial | |
| 1136 | Twin Friends | combinatorics dp | Statement | H | 2023-2024 ICPC, Asia Jakarta Regional Contest (Online Mirror, Unrated, ICPC Rules, Teams Preferred) {1906} | PROGRAMMING | problem_analysis.pdf | ||
| 70 | Inverse Problem | *special combinatorics dp | Statement | I | Kotlin Heroes: Episode 9 (Unrated, T-Shirts + Prizes!) {1910} | PROGRAMMING | 123261 | ||
| 39198 | Erase First or Second Letter | brute force combinatorics dp strings | Statement | B | Codeforces Round 917 (Div. 2) {1917} | PROGRAMMING | 1000.0 | Editorial of Codeforces Round 917 (Div. 2) | |
| 3514 | Counting Binary Strings | combinatorics dp math strings | Statement | E | Codeforces Round 919 (Div. 2) {1920} | PROGRAMMING | 2250.0 | Editorial for Codeforces Round #919 (Div. 2) | |
| 12732 | Chat Screenshots | combinatorics dfs and similar graphs implementation | Statement | F | Codeforces Round 925 (Div. 3) {1931} | PROGRAMMING | 125878 | ||
| 464 | Unique Strings | combinatorics dp math | Statement | F | Educational Codeforces Round 164 (Rated for Div. 2) {1954} | PROGRAMMING | Educational Codeforces Round 164 Editorial | ||
| 5931 | Invertible Bracket Sequences | binary search combinatorics data structures divide and conquer implementation two pointers | Statement | D | Educational Codeforces Round 166 (Rated for Div. 2) {1976} | PROGRAMMING | Educational Codeforces Round 166 Editorial | ||
| 3062 | Cases | bitmasks brute force combinatorics dfs and similar dp graphs greedy strings | Statement | D | Codeforces Round 961 (Div. 2) {1995} | PROGRAMMING | 2250.0 | Video Tutorial | |
| 24083 | Minimise Oneness | brute force combinatorics constructive algorithms | Statement | B | Codeforces Round 979 (Div. 2) {2030} | PROGRAMMING | 500.0 | Codeforces Round 979 Editorial | |
| 2058 | Permutations Harmony | brute force combinatorics constructive algorithms greedy hashing implementation math | Statement | E | Rayan Programming Contest 2024 - Selection (Codeforces Round 989, Div. 1 + Div. 2) {2034} | PROGRAMMING | 2000.0 | Rayan 2024 Selection Round Editorial | |
| 19674 | Replace Character | brute force combinatorics greedy strings | Statement | B | Codeforces Round 990 (Div. 2) {2047} | PROGRAMMING | 1000.0 | Разбор Codeforces Round 990 (Div. 2 + Div. 1) | |
| 2039 | Bro Thinks He's Him | combinatorics data structures dp matrices | Statement | H | Codeforces Round 1003 (Div. 4) {2065} | PROGRAMMING | Video Tutorial | ||
| 31552 | Having Been a Treasurer in the Past, I Help Goblins Deceive | combinatorics constructive algorithms strings | Statement | B | Codeforces Round 1006 (Div. 3) {2072} | PROGRAMMING | Codeforces Round 1006 (Div. 3) Editorial | ||
| 8631 | Even String | combinatorics dp math strings | Statement | D | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 1875 | Binary String Wowee | combinatorics dp strings | Statement | E | Codeforces Round 1025 (Div. 2) {2109} | PROGRAMMING | 2500.0 | Codeforces Round 1025 (Div. 2) Editorial | |
| 1273 | Beyond the Palindrome (Easy Version) | combinatorics dp math | Statement | E1 | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 3000.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 251 | Beyond the Palindrome (Hard Version) | combinatorics dp math number theory | Statement | E2 | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 2000.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 806 | Left is Always Right | combinatorics math | Statement | E | Pinely Round 5 (Div. 1 + Div. 2) {2161} | PROGRAMMING | 3000.0 | ||
| 2474 | Binary Strings and Blocks | combinatorics dp | Statement | E | Educational Codeforces Round 185 (Rated for Div. 2) {2170} | PROGRAMMING | Educational Codeforces Round 185 Editorial | ||
| 1189 | Jumping Man | combinatorics data structures dp trees | Statement | F | Hello 2026 {2183} | PROGRAMMING | 2750.0 | ||
| 2075 | Little String (Hard Version) | binary search combinatorics dp greedy math number theory | Statement | D2 | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 750.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 4252 | Little String (Easy Version) | combinatorics dp math | Statement | D1 | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 2000.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 11597 | Sub-RBS (Easy Version) | combinatorics constructive algorithms dp greedy strings two pointers | Statement | B1 | Codeforces Round 1073 (Div. 1) {2190} | PROGRAMMING | 750.0 | Codeforces Round 1073 (Div. 1, Div. 2) Editorial | |
| 3395 | Sub-RBS (Hard Version) | combinatorics dp games implementation matrices strings | Statement | B2 | Codeforces Round 1073 (Div. 1) {2190} | PROGRAMMING | 750.0 | Codeforces Round 1073 (Div. 1, Div. 2) Editorial | |
| 1222 | Operation Permutation | combinatorics dp math probabilities | Statement | G | Codeforces Round 1084 (Div. 3) {2200} | PROGRAMMING | Codeforces Round 1084 (Div. 3) Editorial | ||
| 235 | Wowee Binary String | combinatorics dp strings | Statement | H | Spectral::Cup 2026 Round 2 (Codeforces Round 1100, Div. 1 + Div. 2) {2229} | PROGRAMMING | 4000.0 | Spectral::Cup 2026 Round 2 (Codeforces Round 1100, Div. 1 + Div. 2) Editorial | |
| 1187 | Permutation Transmission (Easy Version) | combinatorics sortings | Statement | E1 | Educational Codeforces Round 191 (Rated for Div. 2) {2233} | PROGRAMMING | 154371 | ||
| 1166 | Permutation Transmission (Difficult Version) | combinatorics sortings | Statement | E2 | Educational Codeforces Round 191 (Rated for Div. 2) {2233} | PROGRAMMING | 154371 |