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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 3237 | Petr# | brute force data structures hashing strings | Statement | B | Codeforces Beta Round 86 (Div. 1 Only) {113} | PROGRAMMING | Codeforces Beta Round #86 Editorial | 1900 | |
| 13783 | Another Problem on Strings | binary search brute force dp math strings two pointers | Statement | C | Codeforces Round 112 (Div. 2) {165} | PROGRAMMING | Codeforces Round #112 (Div. 2) Tutorial | 1600 | |
| 9228 | Common Divisors | brute force hashing implementation math strings | Statement | D | Codeforces Round 117 (Div. 2) {182} | PROGRAMMING | Codeforces Round #117 (Div. 2) Разбор Задач | 1400 | |
| 603 | Hamming Distance | constructive algorithms greedy math matrices | Statement | C | Codeforces Round 122 (Div. 1) {193} | PROGRAMMING | Editoral Codeforces Round #122 | 2400 | |
| 1232 | Little Elephant and Furik and Rubik | math probabilities | Statement | C | Codeforces Round 129 (Div. 1) {204} | PROGRAMMING | Tutorial | 2200 | |
| 666 | Martian Luck | math number theory | Statement | E | Codeforces Round 133 (Div. 2) {216} | PROGRAMMING | Editorial for Codeforces Round #133 | 2300 | |
| 1212 | 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 | |
| 10812 | Bear and Strings | brute force greedy implementation math strings | Statement | B | Codeforces Round 226 (Div. 2) {385} | PROGRAMMING | Codeforces Round #226 (Div. 2) — Editorial | 1300 | |
| 272 | Hamming Triples | implementation math two pointers | Statement | E | Codeforces Round 238 (Div. 1) {406} | PROGRAMMING | Codeforces Round #238 Tutorial | 2700 | |
| 36817 | Dreamoon and WiFi | bitmasks brute force combinatorics dp math probabilities | Statement | B | Codeforces Round 272 (Div. 2) {476} | PROGRAMMING | 1300 | ||
| 9462 | Hacking Cypher | brute force math number theory strings | Statement | C | Codeforces Round 279 (Div. 2) {490} | PROGRAMMING | Codeforces Round #279 (Div. 2) Editorial | 1700 | |
| 23968 | Anton and currency you all know | greedy math strings | Statement | B | Codeforces Round 288 (Div. 2) {508} | PROGRAMMING | 16048 | 1300 | |
| 1880 | Pretty Song | math strings | Statement | E | Codeforces Round 289 (Div. 2, ACM ICPC Rules) {509} | PROGRAMMING | Tutorial CodeForces Round 289 (Div.2) (Second Winter Computer Camp Selection 2015) | 2000 | |
| 4319 | DNA Alignment | math strings | Statement | C | Codeforces Round 295 (Div. 2) {520} | PROGRAMMING | Codeforces Round #295 Editorial (now with bonuses!) | 1700 | |
| 10212 | Pasha and String | constructive algorithms greedy math strings | Statement | B | Codeforces Round 297 (Div. 2) {525} | PROGRAMMING | Codeforces Round #297 (Div.2) Editorial | 1500 | |
| 14474 | Kyoya and Photobooks | brute force math strings | Statement | A | Codeforces Round 309 (Div. 2) {554} | PROGRAMMING | Codeforces Round #309 Editorial | 900 | |
| 5985 | Barnicle | brute force implementation math strings | Statement | B | Codeforces Round 362 (Div. 2) {697} | PROGRAMMING | 1400 | ||
| 12454 | Passwords | implementation math sortings strings | Statement | B | Codeforces Round 374 (Div. 2) {721} | PROGRAMMING | Codeforces Round #374 (Div. 2) Editorial | 1200 | |
| 2934 | Ability To Convert | constructive algorithms dp greedy math strings | Statement | D | Codeforces Round 392 (Div. 2) {758} | PROGRAMMING | Codeforces Round #392 (Div. 2) Editorial | 1900 | |
| 1198 | Rusty String | fft math strings | Statement | E | Codeforces Round 423 (Div. 1, rated, based on VK Cup Finals) {827} | PROGRAMMING | Codeforces Round #423 Analysis | 2700 | |
| 1234 | String Mark | combinatorics math strings | Statement | D | Codeforces Round 448 (Div. 2) {895} | PROGRAMMING | Codeforces Round #448(Div.2) Editorial | 2300 | |
| 2171 | Kuro and GCD and XOR and SUM | binary search bitmasks brute force data structures dp dsu greedy math number theory strings trees | Statement | D | Codeforces Round 482 (Div. 2) {979} | PROGRAMMING | 1750.0 | Codeforces Round #482 (Div. 2) Editorial | 2200 |
| 11670 | Substring Removal | combinatorics math strings | Statement | B | Educational Codeforces Round 57 (Rated for Div. 2) {1096} | PROGRAMMING | Разбор Educational Codeforces Round 57 | 1400 | |
| 4199 | Circus | brute force greedy math strings | Statement | B | Codeforces Round 545 (Div. 2) {1138} | PROGRAMMING | Codeforces Round #545 – Editorial | 1700 | |
| 4415 | Median String | bitmasks math number theory strings | Statement | E | Codeforces Round 550 (Div. 3) {1144} | PROGRAMMING | 66307 | 1900 | |
| 2380 | The minimal unique substring | constructive algorithms math strings | Statement | B | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 2200 | |
| 154 | Heidi Learns Hashing (Hard) | fft math number theory | Statement | A3 | Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} | PROGRAMMING | helvetic-coding-contest-2019-editorial.pdf | 3100 | |
| 5455 | Print a 1337-string... | combinatorics constructive algorithms math strings | Statement | D | Educational Codeforces Round 70 (Rated for Div. 2) {1202} | PROGRAMMING | 68972 | 1900 | |
| 2763 | You Are Given a WASD-string... | brute force data structures dp greedy implementation math strings | Statement | C | Educational Codeforces Round 70 (Rated for Div. 2) {1202} | PROGRAMMING | 68972 | 2100 | |
| 3390 | Kirk and a Binary String (hard version) | data structures greedy math strings | Statement | D2 | Codeforces Round 581 (Div. 2) {1204} | PROGRAMMING | 69244 | 2100 | |
| 27957 | Prime Subtraction | math number theory | Statement | A | Educational Codeforces Round 74 (Rated for Div. 2) {1238} | PROGRAMMING | Educational Codeforces Round 74 Editorial | 900 | |
| 1334 | Awesome Substrings | math strings | Statement | F | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 2600 | |
| 20659 | Even But Not Even | greedy math strings | Statement | A | Codeforces Round 616 (Div. 2) {1291} | PROGRAMMING | 500.0 | Codeforces Round #616 Editorial | 1000 |
| 9862 | Infinite Prefixes | math strings | Statement | B | Educational Codeforces Round 81 (Rated for Div. 2) {1295} | PROGRAMMING | Educational Codeforces Round 81 Editorial | 1700 | |
| 9860 | 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 |
| 12587 | Cow and Message | brute force dp math strings | Statement | C | Codeforces Round 621 (Div. 1 + Div. 2) {1307} | PROGRAMMING | 1500.0 | Codeforces Round #621 (Div. 1 + Div. 2) Editorial | 1500 |
| 21315 | Codeforces Subsequences | brute force constructive algorithms greedy math strings | Statement | B | Codeforces Global Round 8 {1368} | PROGRAMMING | 1000.0 | Codeforces Global Round 8: editorial | |
| 9747 | Omkar and Bed Wars | constructive algorithms dp greedy math strings | Statement | D | Codeforces Global Round 10 {1392} | PROGRAMMING | 1500.0 | Codeforces Global Round 10 — Editorial | |
| 1005 | Song of the Sirens | divide and conquer hashing math strings | Statement | G | Good Bye 2020 {1466} | PROGRAMMING | 2500.0 | Good Bye 2020 Editorial | |
| 34984 | String LCM | brute force math strings | Statement | B | Educational Codeforces Round 102 (Rated for Div. 2) {1473} | PROGRAMMING | Educational Codeforces Round 102 Editorial | ||
| 86089 | Odd Divisor | bitmasks math number theory | Statement | A | Codeforces Round 697 (Div. 3) {1475} | PROGRAMMING | Codeforces Round #697 (Div. 3) Editorial | ||
| 6662 | Binary Literature | constructive algorithms greedy implementation math strings two pointers | Statement | A | Codeforces Round 715 (Div. 1) {1508} | PROGRAMMING | 750.0 | Codeforces Round #715 Editorial | |
| 541 | Chainword | data structures dp math matrices strings | Statement | F | Educational Codeforces Round 107 (Rated for Div. 2) {1511} | PROGRAMMING | 89634 | ||
| 2791 | Kill Anton | brute force constructive algorithms data structures math strings | Statement | D | Codeforces Round 723 (Div. 2) {1526} | PROGRAMMING | 2250.0 | Codeforces Round #723 (Div. 2) Editorial | |
| 1413 | 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 | |
| 19438 | Make a Power of Two | greedy math strings | Statement | D | Codeforces Round 739 (Div. 3) {1560} | PROGRAMMING | 94009 | 1300 | |
| 41919 | Casimir's String Solitaire | math strings | Statement | A | Codeforces Round 744 (Div. 3) {1579} | PROGRAMMING | Codeforces Round #744 (Div. 3) Editorial | ||
| 28057 | Make Them Equal | brute force greedy math strings | Statement | C | Codeforces Round 747 (Div. 2) {1594} | PROGRAMMING | 1500.0 | 95525 | 1200 |
| 18108 | Blue-Red Permutation | greedy math sortings | Statement | D | Codeforces Round 753 (Div. 3) {1607} | PROGRAMMING | Codeforces Round #753 (Div. 3) Editorial | ||
| 4722 | Reverse | bitmasks implementation math strings | Statement | F | Codeforces Round 760 (Div. 3) {1618} | PROGRAMMING | Codeforces Round #760 (Div. 3) Editorial | ||
| 7262 | BA-String | bitmasks brute force dp greedy implementation math shortest paths | Statement | C | Educational Codeforces Round 119 (Rated for Div. 2) {1620} | PROGRAMMING | 98061 | ||
| 4634 | Shuffle | combinatorics math two pointers | Statement | D | Educational Codeforces Round 120 (Rated for Div. 2) {1622} | PROGRAMMING | Educational Codeforces Round 120 Editorial | ||
| 7040 | Infinite Set | dp math matrices number theory strings | Statement | D | Codeforces Round 772 (Div. 2) {1635} | PROGRAMMING | 2250.0 | Codeforces Round #772 Editorial | |
| 7941 | Promising String (easy version) | brute force implementation math strings | Statement | F1 | Codeforces Round 780 (Div. 3) {1660} | PROGRAMMING | Codeforces Round #780 (Div. 3) Editorial | ||
| 3136 | Promising String (hard version) | data structures implementation math strings | Statement | F2 | Codeforces Round 780 (Div. 3) {1660} | PROGRAMMING | Codeforces Round #780 (Div. 3) Editorial | ||
| 17911 | Social Distance | greedy math sortings | Statement | B | Codeforces Round 783 (Div. 2) {1668} | PROGRAMMING | 500.0 | Codeforces Round #783 Editorial | 900 |
| 21137 | 2-Letter Strings | data structures math strings | Statement | E | Codeforces Round 784 (Div. 4) {1669} | PROGRAMMING | 102101 | 1200 | |
| 34519 | Most Similar Words | brute force greedy implementation implementation math strings | Statement | C | Codeforces Round 790 (Div. 4) {1676} | PROGRAMMING | Codeforces Round #790 (Div. 4) Editorial | ||
| 8733 | Manipulating History | math strings | Statement | C | Codeforces Round 796 (Div. 2) {1688} | PROGRAMMING | 1250.0 | Tutorial | |
| 8838 | Shifting String | graphs math number theory strings | Statement | F | Codeforces Round 797 (Div. 3) {1690} | PROGRAMMING | Codeforces Round #797 (Div. 3) Editorial | 1700 | |
| 17193 | Sum of Substrings | brute force constructive algorithms greedy math strings | Statement | C | CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} | PROGRAMMING | 1250.0 | Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2) | |
| 383 | Long Binary String | math matrices meet-in-the-middle number theory | Statement | G | Codeforces Round 803 (Div. 2) {1698} | PROGRAMMING | 3250.0 | Codeforces Round #803 (Div. 2) Editorial | |
| 9433 | Equate Multisets | constructive algorithms data structures graph matchings greedy math number theory | Statement | F | Codeforces Round 805 (Div. 3) {1702} | PROGRAMMING | 104763 | ||
| 133 | Mio and Lucky Array | constructive algorithms fft math strings | Statement | G | CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} | PROGRAMMING | 3500.0 | CodeTON Round 2 Editorial | |
| 23397 | Add Modulo 10 | brute force math number theory | Statement | E | Codeforces Round 811 (Div. 3) {1714} | PROGRAMMING | Codeforces Round #811 (Div. 3) 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 | |
| 18718 | Prefix Sum Addicts | constructive algorithms math sortings | Statement | B | Codeforces Global Round 22 {1738} | PROGRAMMING | 1000.0 | Editorial of Codeforces Global Round <strong>22</strong> | |
| 9638 | Koxia and Number Theory | chinese remainder theorem math number theory | Statement | C | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 1250.0 | Good Bye 2022 -- Editorial | |
| 3388 | Flexible String Revisit | combinatorics dp math probabilities | Statement | D | Codeforces Round 848 (Div. 2) {1778} | PROGRAMMING | 1750.0 | Codeforces Round #848 (Div. 2) Editorial | |
| 24037 | Hall of Fame | constructive algorithms greedy math strings | Statement | A | Hello 2023 {1779} | PROGRAMMING | 500.0 | ||
| 984 | Delicious Dessert | math number theory string suffix structures strings | Statement | G | Codeforces Round 846 (Div. 2) {1780} | PROGRAMMING | 2500.0 | 111841 | |
| 32616 | Serval and Mocha's Array | brute force math number theory | Statement | A | Codeforces Round 853 (Div. 2) {1789} | PROGRAMMING | 500.0 | Codeforces Round #853 (Div. 2) Editorial | |
| 40830 | Polycarp and the Day of Pi | implementation math strings | Statement | A | Codeforces Round 847 (Div. 3) {1790} | PROGRAMMING | 111948 | ||
| 8009 | Fixed Prefix Permutations | binary search data structures math sortings strings | Statement | D | Educational Codeforces Round 142 (Rated for Div. 2) {1792} | PROGRAMMING | 111835 | ||
| 27659 | Subsequence Addition (Hard Version) | dp greedy implementation math sortings | Statement | G2 | Codeforces Round 859 (Div. 4) {1807} | PROGRAMMING | 114143 | ||
| 34572 | Insert Digit | greedy math strings | Statement | A | Codeforces Round 863 (Div. 3) {1811} | PROGRAMMING | 114788 | ||
| 419 | Bosco and Particle | dp math number theory strings | Statement | E | Codeforces Round 865 (Div. 1) {1815} | PROGRAMMING | 3000.0 | Editorial of Codeforces Round #865 | 3100 |
| 22822 | JoJo's Incredible Adventures | math strings two pointers | Statement | B | Codeforces Round 866 (Div. 2) {1820} | PROGRAMMING | 1000.0 | Codeforces Round #866 (Div.1, Div.2, based on Lipetsk Team Olympiad) Editorial | |
| 16184 | Tear It Apart | brute force implementation math strings | Statement | C | Educational Codeforces Round 147 (Rated for Div. 2) {1821} | PROGRAMMING | 115296 | ||
| 12314 | Making Anti-Palindromes | greedy math strings | Statement | E | Codeforces Round 867 (Div. 3) {1822} | PROGRAMMING | Codeforces Round #867 (Div. 3) Editorial | ||
| 4300 | Unique Palindromes | binary search constructive algorithms greedy math strings | Statement | D | Codeforces Round 868 (Div. 2) {1823} | PROGRAMMING | 2000.0 | 115465 | |
| 9032 | Ranom Numbers | brute force dp greedy math strings | Statement | C | Educational Codeforces Round 150 (Rated for Div. 2) {1841} | PROGRAMMING | 117262 | ||
| 2105 | Omsk Metro (hard version) | data structures dfs and similar divide and conquer dp implementation math trees | Statement | F2 | Codeforces Round 881 (Div. 3) {1843} | PROGRAMMING | Codeforces Round #881 (Div. 3) Editorial | ||
| 6329 | Omsk Metro (simple version) | data structures dfs and similar dp greedy math trees | Statement | F1 | Codeforces Round 881 (Div. 3) {1843} | PROGRAMMING | Codeforces Round #881 (Div. 3) Editorial | ||
| 13810 | 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 | |
| 7373 | Lisa and the Martians | bitmasks data structures greedy math sortings strings trees | Statement | F | Codeforces Round 888 (Div. 3) {1851} | PROGRAMMING | 118667 | ||
| 3035 | 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 | |
| 4920 | Vasilije Loves Number Theory | math number theory | Statement | F | Codeforces Round 900 (Div. 3) {1878} | PROGRAMMING | Codeforces round #900 (Div.3) Editorial | ||
| 28182 | Divide and Equalize | math number theory | Statement | D | Codeforces Round 903 (Div. 3) {1881} | PROGRAMMING | 121327 | ||
| 1253 | Split | binary search data structures divide and conquer math two pointers | Statement | D | Codeforces Round 905 (Div. 1) {1887} | PROGRAMMING | 1250.0 | Codeforces Round #905 (Div. 1, Div. 2, Div. 3) Editorial | |
| 6987 | Ones and Twos | data structures math two pointers | Statement | D | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) {1896} | PROGRAMMING | 2000.0 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 116 | Cyclic Hamming (Easy Version) | divide and conquer dp fft math number theory | Statement | H1 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) {1896} | PROGRAMMING | 4000.0 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 141 | Cyclic Hamming (Hard Version) | dp fft math number theory | Statement | H2 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) {1896} | PROGRAMMING | 1000.0 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 23083 | Removal of Unattractive Pairs | constructive algorithms greedy math strings | Statement | C | Codeforces Round 913 (Div. 3) {1907} | PROGRAMMING | Codeforces Round 913 (Div. 3) Editorial | ||
| 9745 | Mathematical Problem | brute force constructive algorithms implementation math strings | Statement | D | Good Bye 2023 {1916} | PROGRAMMING | 1500.0 | ||
| 28259 | 2023 | constructive algorithms implementation math number theory | Statement | A | Good Bye 2023 {1916} | PROGRAMMING | 250.0 | ||
| 3369 | 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) | |
| 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 | |
| 4528 | Non-Palindromic Substring | data structures hashing implementation math strings | Statement | B | Codeforces Round 934 (Div. 1) {1943} | PROGRAMMING | 1250.0 | Codeforces Round #934 (Div1, Div2) Editorial | |
| 2494 | Division + LCP (hard version) | binary search brute force data structures dp hashing math string suffix structures strings | Statement | G2 | Codeforces Round 943 (Div. 3) {1968} | PROGRAMMING | 129096 | 2200 | |
| 21014 | 378QAQ and Mocha's Array | brute force greedy math sortings | Statement | B | Codeforces Round 947 (Div. 1 + Div. 2) {1975} | PROGRAMMING | 500.0 | editorial_zh.pdf | 1000 |
| 339 | Zimpha Fan Club | fft greedy math strings | Statement | G | Codeforces Round 947 (Div. 1 + Div. 2) {1975} | PROGRAMMING | 3000.0 | editorial_zh.pdf | 3000 |
| 12961 | Permutation of Rows and Columns | constructive algorithms data structures hashing math matrices sortings | Statement | E | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 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 | |
| 27468 | Soccer | greedy implementation math sortings | Statement | A | Codeforces Round 955 (Div. 2, with prizes from NEAR!) {1982} | PROGRAMMING | 500.0 | 130839 | |
| 11001 | Swap Dilemma | constructive algorithms divide and conquer greedy math sortings | Statement | D | Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} | PROGRAMMING | 1750.0 | ||
| 3869 | ''a'' String Problem | hashing implementation math string suffix structures strings | Statement | D | Codeforces Global Round 26 {1984} | PROGRAMMING | 2500.0 | Codeforces Global Round 26 Editorial | |
| 2770 | Triangle Formation | brute force greedy math sortings | Statement | F | Pinely Round 4 (Div. 1 + Div. 2) {1991} | PROGRAMMING | 2500.0 | Video Tutorial | |
| 559 | Prime Split Game | fft games math number theory | Statement | H | Pinely Round 4 (Div. 1 + Div. 2) {1991} | PROGRAMMING | 3500.0 | Video Tutorial | |
| 10727 | Novice's Mistake | brute force constructive algorithms math strings | Statement | E | Codeforces Round 957 (Div. 3) {1992} | PROGRAMMING | Shayan's Video Tutorial | ||
| 7349 | 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 | |
| 43987 | Primary Task | implementation math strings | Statement | A | Codeforces Round 966 (Div. 3) {2000} | PROGRAMMING | 132689 | ||
| 32893 | Square or Not | math strings | Statement | B | Codeforces Round 970 (Div. 3) {2008} | PROGRAMMING | Codeforces Round 970 (Div. 3) Editorial | ||
| 1369 | C+K+S | brute force constructive algorithms dfs and similar graphs greedy hashing math strings | Statement | C | Codeforces Round 980 (Div. 1) {2023} | PROGRAMMING | 1500.0 | 135341 | |
| 20251 | Alice's Adventures in ''Chess'' | brute force implementation math strings | Statement | A | Codeforces Round 986 (Div. 2) {2028} | PROGRAMMING | 500.0 | Codeforces Round 986 (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 | |
| 18894 | Digital string maximization | brute force greedy math strings | Statement | D | Codeforces Round 991 (Div. 3) {2050} | PROGRAMMING | Разбор Codeforces Round 991 (Div. 3) | ||
| 89 | Cosmic Divide | brute force geometry hashing math strings | Statement | F | Codeforces Round 996 (Div. 2) {2055} | PROGRAMMING | 3500.0 | Codeforces Round 996 (Div. 2) Editorial | |
| 27787 | The Play Never Ends | math number theory | Statement | A | Codeforces Round 1007 (Div. 2) {2071} | PROGRAMMING | 500.0 | Codeforces Round 1007 (Div. 2) Editorial | |
| 8330 | Even String | combinatorics dp math strings | Statement | D | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 428 | 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 | |
| 30722 | Simple Repetition | math number theory | Statement | C | Codeforces Round 1016 (Div. 3) {2093} | PROGRAMMING | Codeforces Round 1016 (Div. 3) Editorial | ||
| 529 | Homework | bitmasks math matrices | Statement | D | Codeforces Round 1021 (Div. 1) {2097} | PROGRAMMING | 2000.0 | 142316 | |
| 8490 | Sports Betting | math sortings | Statement | A | Codeforces Round 1021 (Div. 1) {2097} | PROGRAMMING | 500.0 | 142316 | |
| 2026 | Build an Array | bitmasks dp math number theory | Statement | G | Codeforces Round 1027 (Div. 3) {2114} | PROGRAMMING | 143268 | ||
| 30400 | Not Quite a Palindromic String | greedy greedy math math | Statement | B | Codeforces Round 1027 (Div. 3) {2114} | PROGRAMMING | 143268 | ||
| 5331 | Gangsta | data structures divide and conquer math sortings | Statement | G | Codeforces Round 1032 (Div. 3) {2121} | PROGRAMMING | Codeforces Round 1032 (Div. 3) Editorial | ||
| 3223 | Modular Sorting | brute force data structures math number theory | Statement | G | Codeforces Round 1034 (Div. 3) {2123} | PROGRAMMING | Codeforces Round 1034 (Div. 3) Editorial | ||
| 16916 | G-C-D, Unlucky! | math number theory | Statement | E | Codeforces Round 1037 (Div. 3) {2126} | PROGRAMMING | 144845 | ||
| 4699 | Unjust Binary Life | binary search binary search data structures greedy greedy math two pointers | Statement | F | Codeforces Round 1042 (Div. 3) {2131} | PROGRAMMING | Codeforces Round 1042 (Div. 3) Editorial | ||
| 21521 | Make it Equal | math number theory | Statement | C | Codeforces Round 1042 (Div. 3) {2131} | PROGRAMMING | Codeforces Round 1042 (Div. 3) Editorial | ||
| 155 | 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 | |
| 1878 | Make Good | constructive algorithms math strings | Statement | E | Codeforces Round 1051 (Div. 2) {2143} | PROGRAMMING | 2500.0 | Codeforces Round 1051 (Div. 2) Editorial | |
| 19482 | Souvlaki VS. Kalamaki | math sortings | Statement | A | Codeforces Round 1063 (Div. 2) {2163} | PROGRAMMING | 500.0 | Codeforces Round 1063 Editorial | |
| 34164 | Blackslex and Password | math strings | Statement | A | Codeforces Round 1071 (Div. 3) {2179} | PROGRAMMING | Codeforces Round 1071 (Div. 3) Editorial | ||
| 3665 | Alphabet City | binary search math strings | Statement | A | 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} | PROGRAMMING | Tutorial | ||
| 1906 | 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 | |
| 808 | Majority Wins? | dp greedy math strings | Statement | E | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 2500.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 970 | Operation Permutation | combinatorics dp math probabilities | Statement | G | Codeforces Round 1084 (Div. 3) {2200} | PROGRAMMING | Codeforces Round 1084 (Div. 3) Editorial | ||
| 429 | Six Seven | divide and conquer math number theory strings trees | Statement | H | Codeforces Round 1084 (Div. 3) {2200} | PROGRAMMING | Codeforces Round 1084 (Div. 3) Editorial | ||
| 269 | ABBA Counting | fft math number theory strings | Statement | E | Codeforces Round 1082 (Div. 1) {2201} | PROGRAMMING | 3000.0 | Codeforces Round 1082 (Div. 1, Div. 2) Complete Editorial |