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1 2 3 4 5 6 >Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 6923 | Center Alignment | implementation strings | Statement | B | Codeforces Beta Round 5 {5} | PROGRAMMING | C, D и E с CBR5 - разбор | 1400 | |
| 18833 | Longest Regular Bracket Sequence | constructive algorithms data structures dp greedy sortings strings | Statement | C | Codeforces Beta Round 5 {5} | PROGRAMMING | C, D и E с CBR5 - разбор | 1900 | |
| 4726 | Palindrome Degree | hashing strings | Statement | D | Codeforces Beta Round 7 {7} | PROGRAMMING | 2200 | ||
| 6881 | Train and Peter | strings | Statement | A | Codeforces Beta Round 8 {8} | PROGRAMMING | Codeforces Beta Round #8 Tutorial | 1400 | |
| 810 | Beads | dp graphs | Statement | E | Codeforces Beta Round 8 {8} | PROGRAMMING | Codeforces Beta Round #8 Tutorial | 2600 | |
| 1895 | Logging | implementation strings | Statement | D | Codeforces Beta Round 16 (Div. 2 Only) {16} | PROGRAMMING | Codeforces Beta Round #16 Tutorial | 2000 | |
| 1076 | Balance | dp | Statement | C | Codeforces Beta Round 17 {17} | PROGRAMMING | Codeforces Beta Round #17 Tutorial | 2500 | |
| 2164 | Palisection | strings | Statement | E | Codeforces Beta Round 17 {17} | PROGRAMMING | Codeforces Beta Round #17 Tutorial | 2900 | |
| 7243 | BerOS file system | implementation | Statement | A | Codeforces Alpha Round 20 (Codeforces format) {20} | PROGRAMMING | 2600 | ||
| 2314 | Jabber ID | implementation strings | Statement | A | Codeforces Alpha Round 21 (Codeforces format) {21} | PROGRAMMING | 2300 | ||
| 3421 | Test | hashing strings | Statement | E | Codeforces Beta Round 25 (Div. 2 Only) {25} | PROGRAMMING | Codeforces Beta Round #25 Solution Analysis | 2300 | |
| 963 | Tricky and Clever Password | binary search constructive algorithms data structures greedy hashing strings | Statement | E | Codeforces Beta Round 30 (Codeforces format) {30} | PROGRAMMING | Codeforces Beta Round #30. Tutorial for problem A | 2700 | |
| 4801 | Sysadmin Bob | greedy implementation strings | Statement | B | Codeforces Beta Round 31 (Div. 2, Codeforces format) {31} | PROGRAMMING | 1500 | ||
| 6040 | String Problem | shortest paths | Statement | B | Codeforces Beta Round 33 (Codeforces format) {33} | PROGRAMMING | Codeforces Beta Round #33 (personal participation commentaries) | 1800 | |
| 4857 | Page Numbers | expression parsing implementation sortings strings | Statement | C | Codeforces Beta Round 34 (Div. 2) {34} | PROGRAMMING | Codeforces Beta Round #34 (Div. 2) Разбор | 1400 | |
| 2263 | Old Berland Language | data structures greedy trees | Statement | C | Codeforces Beta Round 37 {37} | PROGRAMMING | Codeforces Beta Round #37 (Tutorial) | 1900 | |
| 461 | Smart Boy | dp games strings | Statement | F | School Personal Contest #1 (Winter Computer School 2010/11) - Codeforces Beta Round 38 (ACM-ICPC Rules) {38} | PROGRAMMING | Школьная индивидуальная олимпиада #1 - Codeforces Beta Round #38. (Разбор задачи D) | 2200 | |
| 3635 | Spelling Check | hashing implementation strings | Statement | J | School Team Contest 1 (Winter Computer School 2010/11) {39} | PROGRAMMING | School Team Contest #1 (Winter Computer School 2010/11): Problem K Tutorial | 1600 | |
| 194146 | Translation | implementation strings | Statement | A | Codeforces Beta Round 40 (Div. 2) {41} | PROGRAMMING | Codeforces Beta Round #40 Mini-Tutorial | 900 | |
| 71219 | Football | strings | Statement | A | Codeforces Beta Round 42 (Div. 2) {43} | PROGRAMMING | How to solve Codeforces 42(Div.2) | 1100 | |
| 20882 | Letter | implementation strings | Statement | B | Codeforces Beta Round 42 (Div. 2) {43} | PROGRAMMING | How to solve Codeforces 42(Div.2) | 1200 | |
| 665 | Director | constructive algorithms greedy | Statement | E | School Team Contest 3 (Winter Computer School 2010/11) {45} | PROGRAMMING | 2100 | ||
| 6560 | Choosing Symbol Pairs | strings | Statement | B | Codeforces Beta Round 47 {50} | PROGRAMMING | Round# 47 simple tutorial | 1500 | |
| 738 | Writing a Song | brute force dp strings | Statement | D | Codeforces Beta Round 50 {54} | PROGRAMMING | Codeforces Beta Round #50: Editorial for problem E | 2100 | |
| 159636 | Chat room | greedy strings | Statement | A | Codeforces Beta Round 54 (Div. 2) {58} | PROGRAMMING | Codeforces Beta Round #54 (Div.2) - разбор A-D | 1100 | |
| 865 | Calendar | greedy strings | Statement | D | Codeforces Beta Round 54 (Div. 2) {58} | PROGRAMMING | Codeforces Beta Round #54 (Div.2) - разбор A-D | 2000 | |
| 235608 | Word | implementation strings | Statement | A | Codeforces Beta Round 55 (Div. 2) {59} | PROGRAMMING | Round 55 (DIV 2) | 800 | |
| 4295 | Hard Work | strings | Statement | B | Codeforces Beta Round 57 (Div. 2) {61} | PROGRAMMING | Round 57-A | 1300 | |
| 13621 | Sinking Ship | implementation sortings strings | Statement | A | Codeforces Beta Round 59 (Div. 2) {63} | PROGRAMMING | Разбор задач Codeforces Round #59 (Div. 2) | 1100 | |
| 94 | Sort the Table | *special sortings | Statement | I | Unknown Language Round 1 {64} | PROGRAMMING | 2500 | ||
| 7128 | Petya and Java | implementation strings | Statement | A | Codeforces Beta Round 61 (Div. 2) {66} | PROGRAMMING | Codeforces Beta Round #61 (Div. 2): Editorial | 1400 | |
| 2143 | Text Messaging | expression parsing greedy strings | Statement | B | Codeforces Beta Round 64 {70} | PROGRAMMING | Analysis Codeforces Beta Round #64 | 1600 | |
| 520003 | Way Too Long Words | strings | Statement | A | Codeforces Beta Round 65 (Div. 2) {71} | PROGRAMMING | Разбор задач Codeforces Beta Round #65 (Div. 2) | 800 | |
| 181 | Ali goes shopping | *special brute force strings | Statement | E | Unknown Language Round 2 {72} | PROGRAMMING | 1900 | ||
| 194 | Goshtasp, Vishtasp and Eidi | *special greedy math | Statement | A | Unknown Language Round 2 {72} | PROGRAMMING | 1900 | ||
| 83 | Perse-script | *special expression parsing | Statement | D | Unknown Language Round 2 {72} | PROGRAMMING | 2400 | ||
| 3651 | Facetook Priority Wall | expression parsing implementation strings | Statement | B | Codeforces Beta Round 67 (Div. 2) {75} | PROGRAMMING | Codeforces Beta Round #67 (Div. 2) Editorial | 1500 | |
| 389 | Mutation | bitmasks dp math | Statement | C | All-Ukrainian School Olympiad in Informatics {76} | PROGRAMMING | All-Ukrainian School Olympiad in Informatics: editorial (A,B,C,D,E,F) | 2700 | |
| 15608 | Haiku | implementation strings | Statement | A | Codeforces Beta Round 70 (Div. 2) {78} | PROGRAMMING | Solutions for Codeforces Beta Round #70 (Div. 2) | 1000 | |
| 2145 | Beaver | data structures dp greedy hashing strings two pointers | Statement | C | Codeforces Beta Round 71 {79} | PROGRAMMING | Codeforces Beta Round #71 Editorial | 1800 | |
| 2162 | Sequence Formatting | implementation strings | Statement | B | Yandex.Algorithm Open 2011: Qualification 1 {81} | PROGRAMMING | 1700 | ||
| 585 | Two Subsequences | bitmasks dp | Statement | E | Codeforces Beta Round 72 (Div. 1 Only) {83} | PROGRAMMING | разбор E | 2800 | |
| 958 | Genetic engineering | dp string suffix structures trees | Statement | C | Yandex.Algorithm 2011: Round 2 {86} | PROGRAMMING | Problemset analysis (Yandex, Round 2) | 2400 | |
| 1272 | Vasya and Types | implementation strings | Statement | B | Codeforces Beta Round 73 (Div. 1 Only) {87} | PROGRAMMING | CodeForces Beta Round #73 div. 1 analysis (particulary with div. 2) | 1900 | |
| 5766 | African Crossword | implementation strings | Statement | B | Codeforces Beta Round 74 (Div. 2 Only) {90} | PROGRAMMING | Codeforces Beta Round #74 - Short editorial except Div. 1 E | 1100 | |
| 4017 | Newspaper Headline | greedy strings | Statement | A | Codeforces Beta Round 75 (Div. 1 Only) {91} | PROGRAMMING | Analysis Codeforces Beta Round #75 | 1600 | |
| 469 | Azembler | brute force implementation | Statement | C | Codeforces Beta Round 76 (Div. 1 Only) {93} | PROGRAMMING | Codeforces Beta Round 76 - задача Е div 1 глазами ее автора. | 2400 | |
| 12530 | Restoring Password | implementation strings | Statement | A | Codeforces Beta Round 76 (Div. 2 Only) {94} | PROGRAMMING | Analysis Beta Round #76 (Div. 2-A,B,C) | 1000 | |
| 1871 | Hockey | implementation strings | Statement | A | Codeforces Beta Round 77 (Div. 1 Only) {95} | PROGRAMMING | Codeforces Beta Round #77 - Analysis | 1700 | |
| 198488 | Football | implementation strings | Statement | A | Codeforces Beta Round 77 (Div. 2 Only) {96} | PROGRAMMING | Codeforces Beta Round #77 (Div. 2 Only) Question A - D | 1100 | |
| 7890 | Help Far Away Kingdom | strings | Statement | A | Codeforces Beta Round 78 (Div. 2 Only) {99} | PROGRAMMING | Solution for problem B in round 78 | 1000 | |
| 366 | World of Mouth | *special strings | Statement | D | Unknown Language Round 3 {100} | PROGRAMMING | 1600 | ||
| 4410 | Homework | greedy | Statement | A | Codeforces Beta Round 79 (Div. 1 Only) {101} | PROGRAMMING | Codeforces Beta Round 79, editoral | 1300 | |
| 1073 | Russian Roulette | constructive algorithms greedy | Statement | C | Codeforces Beta Round 80 (Div. 1 Only) {103} | PROGRAMMING | Tutorial | 1900 | |
| 10438 | Palindromic Times | implementation strings | Statement | A | Codeforces Beta Round 83 (Div. 2 Only) {108} | PROGRAMMING | Editorial: Codeforces Beta Round #83 (Dima) | 1100 | |
| 11105 | Lucky String | constructive algorithms strings | Statement | B | Codeforces Beta Round 84 (Div. 2 Only) {110} | PROGRAMMING | Codeforces Beta Round #84 - Analysis | 1100 | |
| 296007 | Petya and Strings | implementation strings | Statement | A | Codeforces Beta Round 85 (Div. 2 Only) {112} | PROGRAMMING | Разбор CFBR #85 Div. 1 C, D | 900 | |
| 2623 | Grammar Lessons | implementation strings | Statement | A | Codeforces Beta Round 86 (Div. 1 Only) {113} | PROGRAMMING | Codeforces Beta Round #86 Editorial | 1600 | |
| 3347 | Petr# | brute force data structures hashing strings | Statement | B | Codeforces Beta Round 86 (Div. 1 Only) {113} | PROGRAMMING | Codeforces Beta Round #86 Editorial | 1900 | |
| 4319 | PFAST Inc. | bitmasks brute force graphs | Statement | B | Codeforces Beta Round 86 (Div. 2 Only) {114} | PROGRAMMING | Codeforces Beta Round #86 Editorial | 1500 | |
| 1751 | Very Interesting Game | brute force number theory | Statement | B | Codeforces Beta Round 88 {117} | PROGRAMMING | Неофициальный разбор Codeforces Beta Round #88 | 1700 | |
| 236754 | String Task | implementation strings | Statement | A | Codeforces Beta Round 89 (Div. 2) {118} | PROGRAMMING | Разбор задач. Codeforces beta round #89. | 1100 | |
| 3014 | Fancy Number | brute force greedy sortings strings | Statement | C | Codeforces Beta Round 89 (Div. 2) {118} | PROGRAMMING | Editorial codeforces beta raund 89. | 1700 | |
| 707 | String Transformation | hashing strings | Statement | D | Codeforces Beta Round 90 {119} | PROGRAMMING | Codeforces Beta Round #90 (editorial) | 2500 | |
| 2840 | Lucky Transformation | strings | Statement | B | Codeforces Beta Round 91 (Div. 1 Only) {121} | PROGRAMMING | Tutorial | 1600 | |
| 13366 | Lucky Substring | brute force implementation | Statement | B | Codeforces Beta Round 91 (Div. 2 Only) {122} | PROGRAMMING | BIT solution for Codeforces #91 E | 1100 | |
| 4082 | Prime Permutation | implementation number theory strings | Statement | A | Codeforces Beta Round 92 (Div. 1 Only) {123} | PROGRAMMING | Codeforces Beta Round #92 - Analysis | 1600 | |
| 1478 | String | string suffix structures | Statement | D | Codeforces Beta Round 92 (Div. 1 Only) {123} | PROGRAMMING | Codeforces Beta Round #92 - Analysis | 2300 | |
| 26098 | Password | binary search dp hashing string suffix structures strings | Statement | B | Codeforces Beta Round 93 (Div. 1 Only) {126} | PROGRAMMING | Tutorial | 1800 | |
| 3530 | Statues | dfs and similar | Statement | A | Codeforces Beta Round 94 (Div. 1 Only) {128} | PROGRAMMING | 3219 | 1500 | |
| 2928 | String | brute force constructive algorithms hashing implementation string suffix structures strings | Statement | B | Codeforces Beta Round 94 (Div. 1 Only) {128} | PROGRAMMING | 3219 | 2200 | |
| 567 | Gnikool Ssalg | *special implementation strings | Statement | B | Unknown Language Round 4 {130} | PROGRAMMING | Unknown Language Round #4: editorial | 1500 | |
| 103223 | cAPS lOCK | implementation strings | Statement | A | Codeforces Beta Round 95 (Div. 2) {131} | PROGRAMMING | Разбор Codeforces Beta Round #95 (Div.2) | 1100 | |
| 460 | Weak Subsequence | combinatorics | Statement | E | Codeforces Beta Round 97 (Div. 1) {135} | PROGRAMMING | Codeforces Beta Round #97: editorial | 2800 | |
| 1734 | Palindromes | dp strings | Statement | D | Codeforces Beta Round 98 (Div. 2) {137} | PROGRAMMING | Codeforces Beta Round #98 (Div. 2): Editorial | 1900 | |
| 1404 | Last Chance | data structures implementation strings | Statement | E | Codeforces Beta Round 98 (Div. 2) {137} | PROGRAMMING | Codeforces Beta Round #98 (Div. 2): Editorial | 2000 | |
| 223 | Hellish Constraints | brute force dp two pointers | Statement | E | Codeforces Beta Round 99 (Div. 1) {138} | PROGRAMMING | Codeforces Beta Round #99: editorial | 2900 | |
| 103992 | Amusing Joke | implementation sortings strings | Statement | A | Codeforces Round 101 (Div. 2) {141} | PROGRAMMING | Codeforces Round #101 (Div. 2) Разбор Задач. | 900 | |
| 5379 | Help Kingdom of Far Far Away 2 | implementation strings | Statement | B | Codeforces Round 102 (Div. 2) {143} | PROGRAMMING | Codeforces Round #102 - Editorial | 1200 | |
| 4278 | Anagram Search | implementation strings | Statement | C | Codeforces Round 103 (Div. 2) {144} | PROGRAMMING | Codeforces Round #103 (Div. 2) Разбор Задач. | 1500 | |
| 8011 | Lucky Conversion | greedy implementation | Statement | A | Codeforces Round 104 (Div. 1) {145} | PROGRAMMING | Codeforces Round #104 - Editorial | 1300 | |
| 4282 | Punctuation | implementation strings | Statement | A | Codeforces Testing Round 4 {147} | PROGRAMMING | 1300 | ||
| 2402 | Martian Clock | implementation | Statement | B | Codeforces Round 106 (Div. 2) {149} | PROGRAMMING | Editorial Round #106 | 1600 | |
| 2580 | Martian Strings | string suffix structures strings | Statement | E | Codeforces Round 106 (Div. 2) {149} | PROGRAMMING | Codeforces Round #106 (Div. 2) Tutorial | 2200 | |
| 5507 | Quantity of Strings | combinatorics dfs and similar graphs math | Statement | B | Codeforces Round 107 (Div. 1) {150} | PROGRAMMING | Tutorial | 1800 | |
| 783 | Mission Impassable | dp strings | Statement | D | Codeforces Round 107 (Div. 1) {150} | PROGRAMMING | Tutorial | 2600 | |
| 6913 | Phone Numbers | implementation strings | Statement | B | Codeforces Round 107 (Div. 2) {151} | PROGRAMMING | Codeforces Round #107. Tutorial. | 1300 | |
| 4352 | Hometask | greedy | Statement | A | Codeforces Round 109 (Div. 1) {154} | PROGRAMMING | Codeforces Round #109: editorial | 1700 | |
| 522 | Flatland Fencing | games math | Statement | D | Codeforces Round 109 (Div. 1) {154} | PROGRAMMING | Codeforces Round #109: editorial | 2300 | |
| 3281 | Message | brute force | Statement | A | Codeforces Round 110 (Div. 1) {156} | PROGRAMMING | Codeforces Round 110 — Разбор задач | 1700 | |
| 2671 | Friends or Not | *special greedy implementation | Statement | A | VK Cup 2012 Qualification Round 2 {159} | PROGRAMMING | Simple solution to vk cup Qualification Round 1 and 2 | 1700 | |
| 3229 | String Manipulation 1.0 | *special binary search brute force data structures strings | Statement | C | VK Cup 2012 Qualification Round 2 {159} | PROGRAMMING | Simple solution to vk cup Qualification Round 1 and 2 | 2000 | |
| 4717 | Palindrome pairs | *special brute force dp strings | Statement | D | VK Cup 2012 Qualification Round 2 {159} | PROGRAMMING | Simple solution to vk cup Qualification Round 1 and 2 | 2000 | |
| 714 | Abracadabra | divide and conquer | Statement | C | VK Cup 2012 Round 1 {161} | PROGRAMMING | VK Cup 2012 Round 1: editorial | 2400 | |
| 3033 | Substring and Subsequence | dp | Statement | A | VK Cup 2012 Round 2 {163} | PROGRAMMING | VK Cup 2012 Round 2 — Разбор | 1900 | |
| 2313 | e-Government | data structures dfs and similar dp strings trees | Statement | E | VK Cup 2012 Round 2 {163} | PROGRAMMING | VK Cup 2012 Round 2 — Разбор | 2800 | |
| 556 | Ancient Berland Hieroglyphs | two pointers | Statement | B | VK Cup 2012 Round 3 {164} | PROGRAMMING | VK Cup 2012 Round 3 — Разбор | 2300 | |
| 14056 | 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 | |
| 1316 | Wizards and Minimal Spell | implementation strings | Statement | B | Codeforces Round 114 (Div. 2) {168} | PROGRAMMING | Codeforces Round #114 — Tutorial | 1700 | |
| 8241 | Phone Code | *special brute force implementation | Statement | A | Croc Champ 2012 - Qualification Round {172} | PROGRAMMING | 1600 | ||
| 316 | BHTML+BCSS | *special dfs and similar expression parsing | Statement | E | Croc Champ 2012 - Qualification Round {172} | PROGRAMMING | 2500 | ||
| 416 | Hyper String | dp | Statement | D | Croc Champ 2012 - Round 2 {176} | PROGRAMMING | Croc Champ 2012 — Round 2 — Editorial | 2500 | |
| 248 | Fibonacci Strings | strings | Statement | G1 | ABBYY Cup 2.0 - Easy {177} | PROGRAMMING | 2300 | ||
| 281 | Fibonacci Strings | matrices strings | Statement | G2 | ABBYY Cup 2.0 - Easy {177} | PROGRAMMING | 2400 | ||
| 464 | Representative Sampling | Statement | F1 | ABBYY Cup 2.0 - Hard {178} | PROGRAMMING | ABBYY Cup 2.0 — Hard: solutions | 2100 | ||
| 392 | Representative Sampling | dp sortings strings | Statement | F2 | ABBYY Cup 2.0 - Hard {178} | PROGRAMMING | ABBYY Cup 2.0 — Hard: solutions | 2400 | |
| 651 | Representative Sampling | Statement | F3 | ABBYY Cup 2.0 - Hard {178} | PROGRAMMING | ABBYY Cup 2.0 — Hard: solutions | 2600 | ||
| 8696 | Letter | dp | Statement | C | Codeforces Round 116 (Div. 2, ACM-ICPC Rules) {180} | PROGRAMMING | 1400 | ||
| 816 | Name | greedy strings | Statement | D | Codeforces Round 116 (Div. 2, ACM-ICPC Rules) {180} | PROGRAMMING | 2000 | ||
| 9368 | 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 | |
| 673 | Headquarters | constructive algorithms math | Statement | A | Croc Champ 2012 - Final {183} | PROGRAMMING | CROC Champ 2012 — Round 3 (Editorial) | 1900 | |
| 18704 | Comparing Strings | implementation strings | Statement | A | Codeforces Round 118 (Div. 2) {186} | PROGRAMMING | Editorial for Round #118 | 1200 | |
| 3262 | STL | dfs and similar | Statement | C | Codeforces Round 120 (Div. 2) {190} | PROGRAMMING | Codeforces Round #120 (Div.2) — editorial | 1700 | |
| 707 | Hamming Distance | constructive algorithms greedy math matrices | Statement | C | Codeforces Round 122 (Div. 1) {193} | PROGRAMMING | Editoral Codeforces Round #122 | 2400 | |
| 5898 | Lexicographically Maximum Subsequence | greedy strings | Statement | A | Codeforces Round 124 (Div. 1) {196} | PROGRAMMING | Разбор задач | 1200 | |
| 644 | The Next Good String | data structures greedy hashing strings | Statement | D | Codeforces Round 124 (Div. 1) {196} | PROGRAMMING | Codeforces Round #124 — editorial | 2600 | |
| 20097 | LLPS | binary search bitmasks brute force greedy implementation strings | Statement | A | Codeforces Round 127 (Div. 2) {202} | PROGRAMMING | 900 | ||
| 1277 | Little Elephant and Furik and Rubik | math probabilities | Statement | C | Codeforces Round 129 (Div. 1) {204} | PROGRAMMING | Tutorial | 2200 | |
| 673 | Little Elephant and Retro Strings | dp | Statement | D | Codeforces Round 129 (Div. 1) {204} | PROGRAMMING | Tutorial | 2400 | |
| 1668 | Little Elephant and Strings | data structures implementation string suffix structures two pointers | Statement | E | Codeforces Round 129 (Div. 1) {204} | PROGRAMMING | Tutorial | 2800 | |
| 107223 | Dubstep | strings | Statement | A | Codeforces Round 130 (Div. 2) {208} | PROGRAMMING | 4930 | 1100 | |
| 1526 | Solitaire | dfs and similar dp | Statement | B | Codeforces Round 130 (Div. 2) {208} | PROGRAMMING | 4930 | 1800 | |
| 406 | Polycarpus is Looking for Good Substrings | bitmasks hashing implementation | Statement | B | VK Cup 2012 Finals (unofficial online-version) {212} | PROGRAMMING | 2300 | ||
| 1036 | Two Permutations | data structures hashing strings | Statement | E | Codeforces Round 131 (Div. 1) {213} | PROGRAMMING | Codeforces Round #131 Tutorial | 2600 | |
| 698 | Periodical Numbers | combinatorics dp number theory | Statement | E | Codeforces Round 132 (Div. 2) {215} | PROGRAMMING | Codeforces Round #132 (Div. 2) Tutorial | 2600 | |
| 700 | Martian Luck | math number theory | Statement | E | Codeforces Round 133 (Div. 2) {216} | PROGRAMMING | Editorial for Codeforces Round #133 | 2300 | |
| 32981 | k-String | implementation strings | Statement | A | Codeforces Round 135 (Div. 2) {219} | PROGRAMMING | User editorial for Codeforces Round #135 (Div. 2) | 1100 | |
| 2041 | Two Strings | data structures dp strings | Statement | B | Codeforces Round 138 (Div. 1) {223} | PROGRAMMING | 2000 | ||
| 2558 | Cyclical Quest | data structures string suffix structures strings | Statement | C | Codeforces Round 146 (Div. 1) {235} | PROGRAMMING | Codeforces Round #146 Tutorial | 2700 | |
| 290038 | Boy or Girl | brute force implementation strings | Statement | A | Codeforces Round 146 (Div. 2) {236} | PROGRAMMING | Codeforces Round #146 Tutorial | 800 | |
| 2048 | Build String | flows graphs | Statement | E | Codeforces Round 147 (Div. 2) {237} | PROGRAMMING | Codeforces Round #147 (Div. 2) Разбор Задач | 2100 | |
| 5550 | Internet Address | implementation strings | Statement | B | CROC-MBTU 2012, Elimination Round (ACM-ICPC) {245} | PROGRAMMING | КРОК-МВТУ 2012, Отборочный раунд (Разбор) | 1100 | |
| 9509 | Queries for Number of Palindromes | dp hashing strings | Statement | H | CROC-MBTU 2012, Elimination Round (ACM-ICPC) {245} | PROGRAMMING | КРОК-МВТУ 2012, Отборочный раунд (Разбор) | 1900 | |
| 1000 | Log Stream Analysis | binary search brute force implementation strings | Statement | F | CROC-MBTU 2012, Elimination Round (ACM-ICPC) {245} | PROGRAMMING | КРОК-МВТУ 2012, Отборочный раунд (Разбор) | 2000 | |
| 2280 | Restoring IPv6 | implementation strings | Statement | B | CROC-MBTU 2012, Final Round (Online version, Div. 2) {250} | PROGRAMMING | CROC-MBTU 2012, Final Round, Editorial | 1500 | |
| 1614 | Anagram | greedy strings | Statement | C | Codeforces Round 155 (Div. 2) {254} | PROGRAMMING | Codeforces Round #155 (Div. 2) — tutorial | 1800 | |
| 10139 | Little Elephant and Chess | brute force strings | Statement | A | Codeforces Round 157 (Div. 2) {259} | PROGRAMMING | Codeforces Round #157 — Editorial | 1100 | |
| 4103 | Ancient Prophesy | brute force implementation strings | Statement | B | Codeforces Round 158 (Div. 2) {260} | PROGRAMMING | Codeforces Round #158 (Div. 2) Tutorial | 1600 | |
| 455 | Colorful Stones | dp two pointers | Statement | D | Codeforces Round 162 (Div. 1) {264} | PROGRAMMING | Tutorial for E | 2400 | |
| 122 | String Theory | Statement | E | Codeforces Round 165 (Div. 1) {269} | PROGRAMMING | Разбор Codeforces Round #165 | 3100 | ||
| 14600 | Good Substrings | data structures strings | Statement | D | Codeforces Round 166 (Div. 2) {271} | PROGRAMMING | editroal | 1800 | |
| 419 | Mirror Room | data structures implementation | Statement | E | Codeforces Round 168 (Div. 1) {274} | PROGRAMMING | Codeforces Round #168 Editorial | 3000 | |
| 3650 | New Problem | brute force strings | Statement | B | Codeforces Round 170 (Div. 2) {278} | PROGRAMMING | Codeforces Round #170 Tutorial | 1500 | |
| 278660 | Word Capitalization | implementation strings | Statement | A | Codeforces Round 172 (Div. 2) {281} | PROGRAMMING | Codeforces Round #172 Editorial | 800 | |
| 10300 | XOR and OR | constructive algorithms implementation math | Statement | C | Codeforces Round 173 (Div. 2) {282} | PROGRAMMING | Round #173 — Editorial | 1600 | |
| 6839 | Polo the Penguin and Strings | greedy | Statement | A | Codeforces Round 177 (Div. 1) {288} | PROGRAMMING | Codeforces Round #177, editorial | 1300 | |
| 3254 | Mysterious strings | *special implementation | Statement | A | April Fools Day Contest 2013 {290} | PROGRAMMING | April Fools Day Contest 2013: editorial | 1400 | |
| 3093 | Command Line Arguments | *special implementation strings | Statement | B | Croc Champ 2013 - Qualification Round {291} | PROGRAMMING | 2000 | ||
| 1646 | Tree-String Problem | *special dfs and similar hashing strings | Statement | E | Croc Champ 2013 - Qualification Round {291} | PROGRAMMING | 2400 | ||
| 1327 | Beautiful IP Addresses | brute force | Statement | C | Croc Champ 2013 - Round 1 {292} | PROGRAMMING | Чемпионат КРОК 2013 — Раунд 1 (Разбор задач) | 2000 | |
| 3224 | Weird Game | games greedy | Statement | A | Croc Champ 2013 - Round 2 {293} | PROGRAMMING | Croc Champ 2013 — Round 2 — Editorial | 1500 | |
| 413 | Shaass and Painter Robot | brute force implementation number theory | Statement | D | Codeforces Round 178 (Div. 2) {294} | PROGRAMMING | Codeforces Round #178 Editorial | 2700 | |
| 2750 | Yaroslav and Two Strings | combinatorics dp | Statement | B | Codeforces Round 179 (Div. 2) {296} | PROGRAMMING | Codeforces Round #179 tutorial | 2000 | |
| 3878 | Parity Game | constructive algorithms | Statement | A | Codeforces Round 180 (Div. 1) {297} | PROGRAMMING | Tutorial for E | 1700 | |
| 511 | Yaroslav and Algorithm | constructive algorithms | Statement | C | Codeforces Round 182 (Div. 1) {301} | PROGRAMMING | Codeforces Round #182 tutorial | 2700 | |
| 5416 | Whose sentence is it? | implementation strings | Statement | A | Codeforces Round 185 (Div. 2) {312} | PROGRAMMING | Codeforces Round #185 Editorial | 1300 | |
| 1652 | Sereja and Periods | binary search dfs and similar strings | Statement | B | Codeforces Round 187 (Div. 1) {314} | PROGRAMMING | Codeforces Round #187 tutorial | 2000 | |
| 1093 | Good Substrings | hashing strings | Statement | G1 | ABBYY Cup 3.0 {316} | PROGRAMMING | 1700 | ||
| 521 | Good Substrings | string suffix structures | Statement | G2 | ABBYY Cup 3.0 {316} | PROGRAMMING | 2200 | ||
| 546 | Good Substrings | string suffix structures | Statement | G3 | ABBYY Cup 3.0 {316} | PROGRAMMING | 2800 | ||
| 8370 | Strings of Power | implementation strings two pointers | Statement | B | Codeforces Round 188 (Div. 2) {318} | PROGRAMMING | 7956 | 1300 | |
| 787 | Have You Ever Heard About the Word? | greedy hashing string suffix structures strings | Statement | D | Codeforces Round 189 (Div. 1) {319} | PROGRAMMING | Codeforces Round #189 — Editorial | 2700 | |
| 1050 | Students' Revenge | data structures greedy sortings | Statement | C | Codeforces Round 193 (Div. 2) {332} | PROGRAMMING | 8447 | 2200 | |
| 355 | Binary Key | dp greedy implementation | Statement | E | Codeforces Round 193 (Div. 2) {332} | PROGRAMMING | 8447 | 2600 | |
| 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 | |
| 284245 | Helpful Maths | greedy implementation sortings strings | Statement | A | Codeforces Round 197 (Div. 2) {339} | PROGRAMMING | Codeforces Round #197 — Tutorial | 900 | |
| 83 | Chain Letter | *special dfs and similar graphs | Statement | D | Friday the 13th, Programmers Day {345} | PROGRAMMING | 2300 | ||
| 105 | Suffix Subgroup | *special strings | Statement | G | Friday the 13th, Programmers Day {345} | PROGRAMMING | 2600 | ||
| 4418 | Lucky Common Subsequence | dp strings | Statement | B | Codeforces Round 201 (Div. 1) {346} | PROGRAMMING | Codeforces Round #201 Editorial | 2000 | |
| 527 | Game with Strings | bitmasks dp games | Statement | B | Codeforces Round 206 (Div. 1) {354} | PROGRAMMING | Codeforces Round #206 — Editorial | 2500 | |
| 2114 | Xenia and Hamming | implementation math | Statement | B | Codeforces Round 207 (Div. 1) {356} | PROGRAMMING | 9210 | 2000 | |
| 596 | Xenia and String Problem | dp hashing implementation string suffix structures strings | Statement | E | Codeforces Round 207 (Div. 1) {356} | PROGRAMMING | 9210 | 2800 | |
| 3913 | Dima and Text Messages | brute force strings | Statement | B | Codeforces Round 208 (Div. 2) {358} | PROGRAMMING | Codeforces Round #208 (Div. 2) Разбор | 1500 | |
| 1277 | Levko and Strings | combinatorics dp | Statement | C | Codeforces Round 210 (Div. 1) {360} | PROGRAMMING | Codeforces Round #210 editorial | 2700 | |
| 874 | Dima and Magic Guitar | brute force implementation math | Statement | E | Codeforces Round 214 (Div. 2) {366} | PROGRAMMING | Codeforces Round #214 (Div. 2) — Tutorial | 2300 | |
| 6243 | Semifinals | implementation sortings | Statement | B | Codeforces Round 222 (Div. 2) {378} | PROGRAMMING | Codeforces Round #222 — Problem Analysis | 1300 | |
| 1683 | New Year Letter | bitmasks brute force dp | Statement | D | Good Bye 2013 {379} | PROGRAMMING | Tutorial Good Bye 2013 | 2000 | |
| 10942 | 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 | |
| 972 | Diverse Substrings | dp strings two pointers | Statement | C | Testing Round 9 {386} | PROGRAMMING | 2100 | ||
| 444 | Word Folding | brute force | Statement | B | Rockethon 2014 {391} | PROGRAMMING | 5.0 | ||
| 188 | Deleting Substrings | Statement | E | Codeforces Round 230 (Div. 1) {392} | PROGRAMMING | 2500.0 | 83942 | ||
| 26431 | Valera and X | implementation | Statement | A | Codeforces Round 237 (Div. 2) {404} | PROGRAMMING | Codeforces Round #237 (Div. 2) Editorial | 1100 | |
| 365 | Hamming Triples | implementation math two pointers | Statement | E | Codeforces Round 238 (Div. 1) {406} | PROGRAMMING | Codeforces Round #238 Tutorial | 2700 | |
| 2638 | The Great Game | *special | Statement | A | April Fools Day Contest 2014 {409} | PROGRAMMING | April Fools Day Contest 2014: editorial | 1700 | |
| 4263 | Pattern | implementation strings | Statement | C | Coder-Strike 2014 - Round 1 {412} | PROGRAMMING | Editorial of Coder-Strike 2014 Round 1 | 1300 | |
| 945 | E-mail Addresses | implementation | Statement | E | Coder-Strike 2014 - Round 1 {412} | PROGRAMMING | Editorial of Coder-Strike 2014 Round 1 | 1800 | |
| 2739 | Match & Catch | dp string suffix structures strings | Statement | D | Codeforces Round 244 (Div. 2) {427} | PROGRAMMING | Codeforces Round #244 (Div. 2) Editorial | 2000 | |
| 12653 | Prefixes and Suffixes | dp string suffix structures strings two pointers | Statement | D | Codeforces Round 246 (Div. 2) {432} | PROGRAMMING | Codeforces Round #246 (Div. 2) Editorial | 2000 | |
| 577 | Tachibana Kanade's Tofu | dp | Statement | E | Codeforces Round 248 (Div. 2) {433} | PROGRAMMING | Codeforces Round #248 Editorial | 2500 | |
| 4299 | Kolya and Tandem Repeat | brute force implementation strings | Statement | B | Codeforces Round 253 (Div. 2) {443} | PROGRAMMING | Codeforces #253 editorial | 1500 | |
| 898 | DZY Loves Strings | binary search hashing strings two pointers | Statement | D | Codeforces Round 254 (Div. 1) {444} | PROGRAMMING | Codeforces Round #254 Editorial | 2400 | |
| 21116 | DZY Loves Strings | greedy implementation | Statement | B | Codeforces Round #FF (Div. 2) {447} | PROGRAMMING | Codeforces Round #FF(255) Editorial | 1000 | |
| 17682 | Suffix Structures | implementation strings | Statement | B | Codeforces Round 256 (Div. 2) {448} | PROGRAMMING | Tutorial | 1400 | |
| 5117 | Count Good Substrings | math | Statement | D | Codeforces Round 258 (Div. 2) {451} | PROGRAMMING | Codeforces Round #258 Editorial | 2100 | |
| 8575 | Eevee | brute force implementation strings | Statement | A | MemSQL Start[c]UP 2.0 - Round 1 {452} | PROGRAMMING | MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials | 1200 | |
| 1227 | Three strings | data structures dsu string suffix structures strings | Statement | E | MemSQL Start[c]UP 2.0 - Round 1 {452} | PROGRAMMING | MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials | 2400 | |
| 7105 | A Lot of Games | dfs and similar dp games implementation strings trees | Statement | B | Codeforces Round 260 (Div. 1) {455} | PROGRAMMING | Codeforces Round #260 — Editorial | 2100 | |
| 716 | Appleman and a Game | binary search shortest paths strings | Statement | E | Codeforces Round 263 (Div. 1) {461} | PROGRAMMING | Tutorial | 3000 | |
| 6270 | No to Palindromes! | greedy strings | Statement | A | Codeforces Round 265 (Div. 1) {464} | PROGRAMMING | Codeforces Round #265 Editorial | 1700 | |
| 1975 | Substitutes in Number | dp | Statement | C | Codeforces Round 265 (Div. 1) {464} | PROGRAMMING | Codeforces Round #265 Editorial | 2200 | |
| 2085 | Fedor and Essay | dfs and similar dp graphs hashing strings | Statement | D | Codeforces Round 267 (Div. 2) {467} | PROGRAMMING | 2100 | ||
| 132 | Hamming Distance | *special | Statement | G | Surprise Language Round 7 {470} | PROGRAMMING | Surprise Language Round #7: editorial | 2500 | |
| 10866 | MUH and Cube Walls | string suffix structures strings | Statement | D | Codeforces Round 269 (Div. 2) {471} | PROGRAMMING | Codeforces Round #269 Editorial | 2000 | |
| 6541 | Design Tutorial: Make It Nondeterministic | greedy | Statement | C | Codeforces Round 270 {472} | PROGRAMMING | Editorial | 1400 | |
| 497 | Design Tutorial: Increase the Constraints | bitmasks data structures fft | Statement | G | Codeforces Round 270 {472} | PROGRAMMING | Editorial | 2800 | |
| 38001 | Dreamoon and WiFi | bitmasks brute force combinatorics dp math probabilities | Statement | B | Codeforces Round 272 (Div. 2) {476} | PROGRAMMING | 1300 | ||
| 2154 | Dreamoon and Strings | dp strings | Statement | E | Codeforces Round 272 (Div. 2) {476} | PROGRAMMING | Editorial | 2600 | |
| 621 | Dreamoon and Binary | dp strings | Statement | D | Codeforces Round 272 (Div. 1) {477} | PROGRAMMING | Разбор (англ.) | 2600 | |
| 1022 | Game with Strings | bitmasks dp probabilities | Statement | C | Codeforces Round 275 (Div. 1) {482} | PROGRAMMING | Codeforces Round #275 Editorial | 2800 | |
| 675 | Strange Sorting | implementation math | Statement | C | Codeforces Round 276 (Div. 1) {484} | PROGRAMMING | Codeforces Round #276 — Editorial | 2600 | |
| 9527 | Hacking Cypher | brute force math number theory strings | Statement | C | Codeforces Round 279 (Div. 2) {490} | PROGRAMMING | Codeforces Round #279 (Div. 2) Editorial | 1700 | |
| 549 | Deciphering | flows graph matchings | Statement | C | Testing Round 11 {491} | PROGRAMMING | 2400 | ||
| 3256 | Obsessive String | dp strings | Statement | B | Codeforces Round 282 (Div. 1) {494} | PROGRAMMING | 15148 | 2300 | |
| 8215 | Removing Columns | brute force constructive algorithms implementation | Statement | C | Codeforces Round 283 (Div. 2) {496} | PROGRAMMING | 15208 | 1600 | |
| 45582 | Lecture | implementation strings | Statement | B | Codeforces Round 284 (Div. 2) {499} | PROGRAMMING | 15353 | 1000 | |
| 19764 | Misha and Changing Handles | data structures dsu strings | Statement | B | Codeforces Round 285 (Div. 2) {501} | PROGRAMMING | Tutorial | 1100 | |
| 1093 | Misha and LCP on Tree | binary search dfs and similar hashing string suffix structures trees | Statement | E | Codeforces Round 285 (Div. 1) {504} | PROGRAMMING | 15743 | 3000 | |
| 6973 | Mr. Kitayuta's Gift | brute force implementation strings | Statement | A | Codeforces Round 286 (Div. 2) {505} | PROGRAMMING | Tutorial | 1200 | |
| 1023 | Mr. Kitayuta's Gift | combinatorics dp matrices strings | Statement | E | Codeforces Round 286 (Div. 1) {506} | PROGRAMMING | Editorial | 2900 | |
| 24167 | Anton and currency you all know | greedy math strings | Statement | B | Codeforces Round 288 (Div. 2) {508} | PROGRAMMING | 16048 | 1300 | |
| 4390 | Tanya and Password | dfs and similar graphs | Statement | D | Codeforces Round 288 (Div. 2) {508} | PROGRAMMING | 16048 | 2900 | |
| 1910 | 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 | |
| 8406 | Watto and Mechanism | binary search data structures hashing string suffix structures strings | Statement | C | Codeforces Round 291 (Div. 2) {514} | PROGRAMMING | Codeforces Round #291 (Div. 2) Editorial | 1900 | |
| 8440 | Tanya and Postcard | greedy implementation strings | Statement | B | Codeforces Round 293 (Div. 2) {518} | PROGRAMMING | Codeforces Round #293 (Div.2) Editorial | 1500 | |
| 9588 | Vitaly and Strings | constructive algorithms strings | Statement | A | Codeforces Round 293 (Div. 2) {518} | PROGRAMMING | Codeforces Round #293 (Div.2) Editorial | 1600 | |
| 6937 | A and B and Interesting Substrings | data structures dp two pointers | Statement | D | Codeforces Round 294 (Div. 2) {519} | PROGRAMMING | Editorial | 1900 | |
| 4342 | DNA Alignment | math strings | Statement | C | Codeforces Round 295 (Div. 2) {520} | PROGRAMMING | Codeforces Round #295 Editorial (now with bonuses!) | 1700 | |
| 131380 | Pangram | implementation strings | Statement | A | Codeforces Round 295 (Div. 2) {520} | PROGRAMMING | Codeforces Round #295 Editorial (now with bonuses!) | 900 | |
| 19330 | Reposts | *special dfs and similar dp graphs trees | Statement | A | VK Cup 2015 - Qualification Round 1 {522} | PROGRAMMING | Разбор задач VK Cup 2015 — Квалификация 1 | 1700 | |
| 2616 | Name Quest | *special greedy | Statement | C | VK Cup 2015 - Qualification Round 2 {523} | PROGRAMMING | Разбор задач VK Cup 2015 — Квалификация 2 | 1800 | |
| 645 | And Yet Another Bracket Sequence | data structures greedy hashing string suffix structures strings | Statement | F | VK Cup 2015 - Round 1 {524} | PROGRAMMING | VK Cup Round 1 (+ online mirror) editorial | 2700 | |
| 16579 | Vitaliy and Pie | greedy hashing strings | Statement | A | Codeforces Round 297 (Div. 2) {525} | PROGRAMMING | Codeforces Round #297 (Div.2) Editorial | 1200 | |
| 10327 | Pasha and String | constructive algorithms greedy math strings | Statement | B | Codeforces Round 297 (Div. 2) {525} | PROGRAMMING | Codeforces Round #297 (Div.2) Editorial | 1500 | |
| 2531 | Om Nom and Necklace | hashing string suffix structures strings | Statement | D | ZeptoLab Code Rush 2015 {526} | PROGRAMMING | ZeptoLab Code Rush 2015 — Editorial | 2200 | |
| 4081 | Error Correct System | greedy | Statement | B | Codeforces Round 296 (Div. 2) {527} | PROGRAMMING | Codeforces Round #296 Editorial | 1500 | |
| 2984 | Fuzzy Search | bitmasks brute force fft | Statement | D | Codeforces Round 296 (Div. 1) {528} | PROGRAMMING | Codeforces Round #296 Editorial | 2500 | |
| 568 | Levenshtein distance | *special | Statement | G | VK Cup 2015 - Wild Card Round 1 {530} | PROGRAMMING | VK Cup 2015 Wild Card Round 1: editorial | 2300 | |
| 2454 | Correcting Mistakes | constructive algorithms dp greedy hashing strings two pointers | Statement | E | VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) {533} | PROGRAMMING | Разбор VK Cup Round 2 | 1800 | |
| 2725 | Work Group | dfs and similar dp graphs strings trees | Statement | B | VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) {533} | PROGRAMMING | 2000 | ||
| 1000 | Encoding | hashing string suffix structures strings | Statement | F | VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) {533} | PROGRAMMING | Разбор VK Cup Round 2 | 2400 | |
| 4876 | Tavas and Malekas | greedy hashing string suffix structures strings | Statement | D | Codeforces Round 299 (Div. 2) {535} | PROGRAMMING | Codeforces Round #299 Editorial | 2100 | |
| 554 | Tavas on the Path | data structures divide and conquer trees | Statement | E | Codeforces Round 299 (Div. 1) {536} | PROGRAMMING | Codeforces Round #299 Editorial | 3100 | |
| 1602 | Remembering Strings | bitmasks dp | Statement | C | Codeforces Round 302 (Div. 1) {543} | PROGRAMMING | Editorial Codeforces Round #302 | 2600 | |
| 8881 | Set of Strings | implementation strings | Statement | A | Codeforces Round 302 (Div. 2) {544} | PROGRAMMING | Editorial Codeforces Round #302 | 1100 | |
| 12289 | Equidistant String | greedy | Statement | B | Codeforces Round 303 (Div. 2) {545} | PROGRAMMING | Codeforces Round #303 (Div.2) editorial | 1200 | |
| 2738 | Mike and Friends | data structures string suffix structures strings trees | Statement | E | Codeforces Round 305 (Div. 1) {547} | PROGRAMMING | Codeforces Round #305 Editorial | 2800 | |
| 10378 | Mike and Fax | brute force implementation strings | Statement | A | Codeforces Round 305 (Div. 2) {548} | PROGRAMMING | Codeforces Round #305 Editorial | 1200 | |
| 10284 | Face Detection | implementation strings | Statement | A | Looksery Cup 2015 {549} | PROGRAMMING | Looksery Cup 2015 Editorial | 1000 | |
| 44409 | Two Substrings | brute force dp greedy implementation strings | Statement | A | Codeforces Round 306 (Div. 2) {550} | PROGRAMMING | Разбор задач Codeforces Round #306 (Div. 2) | 1500 | |
| 4070 | ZgukistringZ | brute force constructive algorithms implementation strings | Statement | B | Codeforces Round 307 (Div. 2) {551} | PROGRAMMING | Tutorial | 1800 |