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1 2 3 4 >Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 5656 | Line | math number theory | Statement | C | Codeforces Beta Round 7 {7} | PROGRAMMING | 1800 | ||
| 1778 | Digital Root | number theory | Statement | C | Codeforces Beta Round 10 {10} | PROGRAMMING | 2000 | ||
| 5496 | Monitor | binary search number theory | Statement | C | Codeforces Beta Round 16 (Div. 2 Only) {16} | PROGRAMMING | Codeforces Beta Round #16 Tutorial | 1800 | |
| 22149 | Noldbach problem | brute force math number theory | Statement | A | Codeforces Beta Round 17 {17} | PROGRAMMING | Codeforces Beta Round #17 Tutorial | 1100 | |
| 1384 | Notepad | number theory | Statement | D | Codeforces Beta Round 17 {17} | PROGRAMMING | Codeforces Beta Round #17 Tutorial | 2300 | |
| 44532 | Almost Prime | number theory | Statement | A | Codeforces Beta Round 26 (Codeforces format) {26} | PROGRAMMING | Codeforces Beta Round #26 tutorial | 2400 | |
| 4974 | Number With The Given Amount Of Divisors | brute force dp number theory | Statement | E | Codeforces Beta Round 27 (Codeforces format, Div. 2) {27} | PROGRAMMING | Solution of ABC @ Round#27 | 2100 | |
| 720 | Moon Craters | dp sortings | Statement | C | School Team Contest 1 (Winter Computer School 2010/11) {39} | PROGRAMMING | School Team Contest #1 (Winter Computer School 2010/11): Tutorial | 2300 | |
| 1290 | Prime Problem | number theory | Statement | G | School Team Contest 3 (Winter Computer School 2010/11) {45} | PROGRAMMING | 2300 | ||
| 1729 | First Digit Law | dp math probabilities | Statement | C | Codeforces Beta Round 50 {54} | PROGRAMMING | Codeforces Beta Round #50: Editorial for problem E | 2000 | |
| 4847 | Beautiful numbers | dp number theory | Statement | D | Codeforces Beta Round 51 {55} | PROGRAMMING | Round 51, A | 2400 | |
| 8107 | Fortune Telling | implementation number theory | Statement | B | Codeforces Beta Round 55 (Div. 2) {59} | PROGRAMMING | Round 55 (DIV 2) | 1200 | |
| 139547 | Ultra-Fast Mathematician | implementation | Statement | A | Codeforces Beta Round 57 (Div. 2) {61} | PROGRAMMING | Round 57-A | 900 | |
| 2038 | Harry Potter and Three Spells | implementation math | Statement | A | Codeforces Beta Round 60 {65} | PROGRAMMING | Codeforces Beta Round #60: tutorial | 1800 | |
| 3757 | Petya and His Friends | constructive algorithms math number theory | Statement | D | Codeforces Beta Round 61 (Div. 2) {66} | PROGRAMMING | Codeforces Beta Round #61 (Div. 2): Editorial | 1700 | |
| 5422 | Irrational problem | implementation number theory | Statement | A | Codeforces Beta Round 62 {68} | PROGRAMMING | Разбор задачи D. CF62 | 1100 | |
| 7413 | Round Table Knights | dp math number theory | Statement | C | Codeforces Beta Round 65 (Div. 2) {71} | PROGRAMMING | Разбор задач Codeforces Beta Round #65 (Div. 2) | 1600 | |
| 435 | Morrowindows | math number theory | Statement | E | Codeforces Beta Round 66 {73} | PROGRAMMING | Codeforces Beta Round #66 editorial: Problems D, E, F | 2300 | |
| 1447 | Chessboard Billiard | dfs and similar dsu graphs number theory | Statement | C | Codeforces Beta Round 68 {74} | PROGRAMMING | Solutions for Codeforces Beta Round #68 | 2100 | |
| 16355 | Modified GCD | binary search number theory | Statement | C | Codeforces Beta Round 67 (Div. 2) {75} | PROGRAMMING | Codeforces Beta Round #67 (Div. 2), my solutions | 1600 | |
| 824 | Mice | greedy two pointers | Statement | B | All-Ukrainian School Olympiad in Informatics {76} | PROGRAMMING | All-Ukrainian School Olympiad in Informatics: editorial (A,B,C,D,E,F) | 2200 | |
| 2226 | Beaver Game | dp games number theory | Statement | C | Codeforces Beta Round 70 (Div. 2) {78} | PROGRAMMING | Solutions for Codeforces Beta Round #70 (Div. 2) | 1900 | |
| 1090 | Numbers | dp math number theory | Statement | D | Codeforces Beta Round 72 (Div. 1 Only) {83} | PROGRAMMING | разбор E | 2400 | |
| 16753 | Toy Army | math number theory | Statement | A | Codeforces Beta Round 72 (Div. 2 Only) {84} | PROGRAMMING | 1000 | ||
| 467 | Tetris revisited | constructive algorithms graph matchings greedy math | Statement | B | Yandex.Algorithm 2011: Round 2 {86} | PROGRAMMING | Problemset analysis (Yandex, Round 2) | 2100 | |
| 555 | Lostborn | dp math number theory | Statement | E | Codeforces Beta Round 76 (Div. 1 Only) {93} | PROGRAMMING | Codeforces Beta Round 76 - задача Е div 1 глазами ее автора. | 2600 | |
| 4155 | Petya and Divisors | binary search data structures number theory | Statement | B | Codeforces Beta Round 85 (Div. 1 Only) {111} | PROGRAMMING | Codeforces Beta Round #85: Разбор задач | 1900 | |
| 1500 | Double Happiness | brute force math number theory | Statement | C | Codeforces Beta Round 86 (Div. 1 Only) {113} | PROGRAMMING | Codeforces Beta Round #86 Editorial | 2200 | |
| 1750 | Very Interesting Game | brute force number theory | Statement | B | Codeforces Beta Round 88 {117} | PROGRAMMING | Неофициальный разбор Codeforces Beta Round #88 | 1700 | |
| 1474 | Lucky Permutation | brute force combinatorics number theory | Statement | C | Codeforces Beta Round 91 (Div. 1 Only) {121} | PROGRAMMING | Разбор задач | 2000 | |
| 153209 | Lucky Division | brute force number theory | Statement | A | Codeforces Beta Round 91 (Div. 2 Only) {122} | PROGRAMMING | BIT solution for Codeforces #91 E | 1000 | |
| 4078 | Prime Permutation | implementation number theory strings | Statement | A | Codeforces Beta Round 92 (Div. 1 Only) {123} | PROGRAMMING | Codeforces Beta Round #92 - Analysis | 1600 | |
| 12780 | The World is a Theatre | combinatorics math | Statement | C | Codeforces Beta Round 95 (Div. 2) {131} | PROGRAMMING | Разбор Codeforces Beta Round #95 (Div.2) | 1500 | |
| 2538 | Pairs of Numbers | brute force dfs and similar math number theory | Statement | B | Codeforces Testing Round 3 {134} | PROGRAMMING | 1800 | ||
| 8705 | Win or Freeze | games math number theory | Statement | A | Codeforces Round 107 (Div. 1) {150} | PROGRAMMING | Tutorial | 1600 | |
| 6267 | Colliders | math number theory | Statement | B | Codeforces Round 109 (Div. 1) {154} | PROGRAMMING | Codeforces Round #109: editorial | 1700 | |
| 6541 | Ice Sculptures | *special brute force number theory | Statement | D | VK Cup 2012 Qualification Round 1 {158} | PROGRAMMING | Simple solution to vk cup Qualification Round 1 and 2 | 1900 | |
| 1492 | ucyhf | *special brute force implementation number theory | Statement | F | April Fools Day Contest {171} | PROGRAMMING | April Fools Day Contest: editorial | 1700 | |
| 3178 | Pseudorandom Sequence Period | *special implementation number theory | Statement | B | Croc Champ 2012 - Qualification Round {172} | PROGRAMMING | 1800 | ||
| 1533 | Calendar Reform | *special number theory | Statement | D | Croc Champ 2012 - Qualification Round {172} | PROGRAMMING | 1900 | ||
| 5162 | Rectangular Game | number theory | Statement | B1 | ABBYY Cup 2.0 - Easy {177} | PROGRAMMING | 1000 | ||
| 3409 | Rectangular Game | number theory | Statement | B2 | ABBYY Cup 2.0 - Easy {177} | PROGRAMMING | 1200 | ||
| 488 | Divisibility Rules | math number theory | Statement | B | Codeforces Round 116 (Div. 2, ACM-ICPC Rules) {180} | PROGRAMMING | 2300 | ||
| 538 | Visit of the Great | math number theory | Statement | D | Codeforces Round 118 (Div. 1) {185} | PROGRAMMING | Tutorial | 2600 | |
| 420 | Metro Scheme | graphs greedy | Statement | D | Codeforces Round 121 (Div. 1) {191} | PROGRAMMING | Разбор Codeforces Round #121 | 2800 | |
| 30799 | 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 | |
| 374 | 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 | |
| 697 | 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 | |
| 3022 | Reducing Fractions | implementation math number theory sortings | Statement | C | Codeforces Round 137 (Div. 2) {222} | PROGRAMMING | Разбор задач Codeforces Round #137 (Div. 2) | 2000 | |
| 1762 | Partial Sums | combinatorics math number theory | Statement | C | Codeforces Round 138 (Div. 1) {223} | PROGRAMMING | Tutorial | 2200 | |
| 3413 | Well-known Numbers | binary search greedy number theory | Statement | B | Codeforces Round 139 (Div. 2) {225} | PROGRAMMING | 1600 | ||
| 926 | Unsolvable | math number theory | Statement | E | Codeforces Round 139 (Div. 2) {225} | PROGRAMMING | Tutorial | 2100 | |
| 1045 | Anniversary | data structures implementation math matrices number theory | Statement | C | Codeforces Round 140 (Div. 1) {226} | PROGRAMMING | Codeforces Round #140 Editorial | 2100 | |
| 617 | Gifts | combinatorics dp math probabilities | Statement | E | Codeforces Round 142 (Div. 1) {229} | PROGRAMMING | Codeforces Round #142 Problem Analysis | 2500 | |
| 99386 | T-primes | binary search implementation math number theory | Statement | B | Codeforces Round 142 (Div. 2) {230} | PROGRAMMING | Codeforces Round #142 Problem Analysis | 1300 | |
| 21464 | LCM Challenge | number theory | Statement | A | Codeforces Round 146 (Div. 1) {235} | PROGRAMMING | Codeforces Round #146 Tutorial | 1600 | |
| 962 | Number Challenge | combinatorics dp implementation math number theory | Statement | E | Codeforces Round 146 (Div. 1) {235} | PROGRAMMING | Codeforces Round #146 Tutorial | 2600 | |
| 17506 | Easy Number Challenge | implementation number theory | Statement | B | Codeforces Round 146 (Div. 2) {236} | PROGRAMMING | Codeforces Round #146 Tutorial | 1300 | |
| 6840 | Primes on Interval | binary search number theory two pointers | Statement | C | Codeforces Round 147 (Div. 2) {237} | PROGRAMMING | Codeforces Round #147 (Div. 2) Разбор Задач | 1600 | |
| 1360 | Hydra | graphs sortings | Statement | B | Codeforces Round 150 (Div. 1) {243} | PROGRAMMING | Editorial for Codeforces Round #150 | 2100 | |
| 10311 | Buggy Sorting | constructive algorithms greedy sortings | Statement | A | Codeforces Round 151 (Div. 2) {246} | PROGRAMMING | Codeforces Round #151 (Div. 2) Tutorial | 1000 | |
| 5870 | Chilly Willy | math number theory | Statement | B | Codeforces Round 152 (Div. 2) {248} | PROGRAMMING | Разбор задач Codeforces Round #152 | 1400 | |
| 1160 | Number Transformation | dp greedy number theory | Statement | C | Codeforces Round 153 (Div. 1) {251} | PROGRAMMING | Editorial of Codeforces Round #153 | 2500 | |
| 12330 | Good Sequences | dp number theory | Statement | B | Codeforces Round 162 (Div. 1) {264} | PROGRAMMING | Tutorial | 1700 | |
| 9735 | Subtractions | math number theory | Statement | A | Codeforces Testing Round 5 {267} | PROGRAMMING | 1100 | ||
| 122 | String Theory | Statement | E | Codeforces Round 165 (Div. 1) {269} | PROGRAMMING | Разбор Codeforces Round #165 | 3100 | ||
| 15758 | Prime Matrix | binary search brute force math number theory | Statement | B | Codeforces Round 166 (Div. 2) {271} | PROGRAMMING | editroal | 1400 | |
| 684 | Three Horses | constructive algorithms math number theory | Statement | E | Codeforces Round 166 (Div. 2) {271} | PROGRAMMING | 6662 | 2500 | |
| 1628 | Beautiful Decomposition | dp games greedy number theory | Statement | E | Codeforces Round 171 (Div. 2) {279} | PROGRAMMING | Codeforces Round #171 (Div. 2) Разбор Задач | 2100 | |
| 718 | Cows and Cool Sequences | dp math number theory | Statement | D | Codeforces Round 174 (Div. 1) {283} | PROGRAMMING | Editorial for Codeforces #174 | 2400 | |
| 7433 | Cows and Primitive Roots | implementation math number theory | Statement | A | Codeforces Round 174 (Div. 2) {284} | PROGRAMMING | Editorial for Codeforces #174 | 1400 | |
| 698 | Cube Problem | brute force math number theory | Statement | C | Croc Champ 2013 - Round 2 {293} | PROGRAMMING | Croc Champ 2013 — Round 2 — Editorial | 2300 | |
| 4459 | Shaass and Lights | combinatorics number theory | Statement | C | Codeforces Round 178 (Div. 2) {294} | PROGRAMMING | Codeforces Round #178 Editorial | 1900 | |
| 413 | Shaass and Painter Robot | brute force implementation number theory | Statement | D | Codeforces Round 178 (Div. 2) {294} | PROGRAMMING | Codeforces Round #178 Editorial | 2700 | |
| 9554 | Ksusha and Array | brute force number theory sortings | Statement | A | Croc Champ 2013 - Round 2 (Div. 2 Edition) {299} | PROGRAMMING | Croc Champ 2013 — Round 2 — Editorial | 1000 | |
| 1137 | Empire Strikes Back | binary search math number theory | Statement | E | Codeforces Round 181 (Div. 2) {300} | PROGRAMMING | English Tutorial | 2400 | |
| 434 | Rotatable Number | math number theory | Statement | D | Codeforces Round 183 (Div. 1) {303} | PROGRAMMING | Codeforces Round #183 Editorial | 2500 | |
| 988 | Minimum Modular | brute force graphs math number theory | Statement | C | Codeforces Round 183 (Div. 1) {303} | PROGRAMMING | Codeforces Round #183 Editorial | 2700 | |
| 662 | White, Black and White Again | combinatorics number theory | Statement | C | Testing Round 6 {306} | PROGRAMMING | 2200 | ||
| 66206 | Ilya and Bank Account | implementation number theory | Statement | A | Codeforces Round 186 (Div. 2) {313} | PROGRAMMING | Tutorial | 900 | |
| 2672 | 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 | |
| 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 | |
| 10144 | Routine Problem | greedy math number theory | Statement | B | Codeforces Round 196 (Div. 2) {337} | PROGRAMMING | Codeforces Round #196 — Problems Analysis | 1400 | |
| 5265 | Quiz | binary search greedy math matrices number theory | Statement | C | Codeforces Round 196 (Div. 2) {337} | PROGRAMMING | Codeforces Round #196 — Problems Analysis | 1700 | |
| 1155 | Divisor Tree | brute force number theory trees | Statement | E | Codeforces Round 196 (Div. 2) {337} | PROGRAMMING | Codeforces Round #196 — Problems Analysis | 2400 | |
| 1470 | GCD Table | chinese remainder theorem math number theory | Statement | D | Codeforces Round 196 (Div. 1) {338} | PROGRAMMING | Codeforces Round #196 — Problems Analysis | 2700 | |
| 10175 | Rational Resistance | math number theory | Statement | A | Codeforces Round 200 (Div. 1) {343} | PROGRAMMING | Codeforces Round #200 Tutorial | 1600 | |
| 9406 | Alice and Bob | games math number theory | Statement | A | Codeforces Round 201 (Div. 1) {346} | PROGRAMMING | Codeforces Round #201 Editorial | 1600 | |
| 344 | Doodle Jump | math number theory | Statement | E | Codeforces Round 201 (Div. 1) {346} | PROGRAMMING | Codeforces Round #201 Editorial | 3000 | |
| 2316 | Apple Tree | dfs and similar number theory trees | Statement | B | Codeforces Round 202 (Div. 1) {348} | PROGRAMMING | Editorial for Codeforces Round #202 | 2400 | |
| 5293 | Find Maximum | implementation math number theory | Statement | C | Codeforces Round 205 (Div. 2) {353} | PROGRAMMING | 9145 | 1600 | |
| 3382 | Vasya and Beautiful Arrays | brute force dp number theory | Statement | C | Codeforces Round 206 (Div. 1) {354} | PROGRAMMING | Codeforces Round #206 — Editorial | 2000 | |
| 3613 | Prime Number | math number theory | Statement | C | Codeforces Round 209 (Div. 2) {359} | PROGRAMMING | Editorial Codeforces Round #209 (Div. 2) | 2000 | |
| 521 | Levko and Sets | number theory | Statement | D | Codeforces Round 210 (Div. 1) {360} | PROGRAMMING | Codeforces Round #210 editorial | 2600 | |
| 8841 | Levko and Permutation | constructive algorithms math number theory | Statement | B | Codeforces Round 210 (Div. 2) {361} | PROGRAMMING | Codeforces Round #210 editorial | 1200 | |
| 656 | Beautiful Set | brute force number theory | Statement | C | Codeforces Round 213 (Div. 1) {364} | PROGRAMMING | Codeforces Round #213 Editorial | 2500 | |
| 12667 | Fox Dividing Cheese | math number theory | Statement | B | Codeforces Round 218 (Div. 2) {371} | PROGRAMMING | Codeforces Round #218 (Div. 2): Tutorial | 1400 | |
| 5392 | Divisible by Seven | math number theory | Statement | A | Codeforces Round 221 (Div. 1) {375} | PROGRAMMING | Codeforces Round #221 Tutorial | 1800 | |
| 9291 | Tree and Queries | data structures dfs and similar trees | Statement | D | Codeforces Round 221 (Div. 1) {375} | PROGRAMMING | Codeforces Round #221 Tutorial | 2400 | |
| 10767 | 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 | |
| 525 | Fox and Perfect Sets | math | Statement | D | Codeforces Round 228 (Div. 1) {388} | PROGRAMMING | Codeforces Round #228 — Editorial | 2700 | |
| 1650 | On Number of Decompositions into Multipliers | combinatorics math number theory | Statement | A | Codeforces Round 232 (Div. 1) {396} | PROGRAMMING | 500.0 | Codeforces Round #232 Editorial (restored) | |
| 1848 | On Changing Tree | data structures graphs trees | Statement | C | Codeforces Round 232 (Div. 1) {396} | PROGRAMMING | 1500.0 | Codeforces Round #232 Editorial (restored) | |
| 1195 | On Sum of Fractions | math number theory | Statement | B | Codeforces Round 232 (Div. 1) {396} | PROGRAMMING | 1000.0 | Codeforces Round #232 Editorial (restored) | |
| 222 | Tree and Array | constructive algorithms | Statement | C | Codeforces Round 233 (Div. 1) {398} | PROGRAMMING | 1500.0 | Codeforces Round #233 Editorial | |
| 4731 | Roman and Numbers | bitmasks brute force combinatorics dp number theory | Statement | D | Codeforces Round 235 (Div. 2) {401} | PROGRAMMING | Codeforces Round #235 (Div. 2) — Tutorial | 2000 | |
| 2803 | Upgrading Array | dp greedy math number theory | Statement | D | Codeforces Round 236 (Div. 2) {402} | PROGRAMMING | Editorial Codeforces Round #236 | 2000 | |
| 30423 | Mashmokh and ACM | combinatorics dp number theory | Statement | B | Codeforces Round 240 (Div. 1) {414} | PROGRAMMING | Codeforces Round #240 Editorial | 1500 | |
| 10613 | Mashmokh and Numbers | constructive algorithms number theory | Statement | A | Codeforces Round 240 (Div. 1) {414} | PROGRAMMING | Codeforces Round #240 Editorial | 1500 | |
| 1162 | Population Size | greedy implementation math | Statement | D | Codeforces Round 241 (Div. 2) {416} | PROGRAMMING | Codeforces Round #241 — editorial | 2300 | |
| 2336 | The Child and Binary Tree | combinatorics divide and conquer fft number theory | Statement | E | Codeforces Round 250 (Div. 1) {438} | PROGRAMMING | Tutorial | 3100 | |
| 4188 | 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 | |
| 9064 | Forgotten Episode | implementation | Statement | A | Testing Round 10 {440} | PROGRAMMING | 1000 | ||
| 4072 | DZY Loves Fibonacci Numbers | data structures math number theory | Statement | C | Codeforces Round #FF (Div. 1) {446} | PROGRAMMING | Codeforces Round #FF(255) Editorial | 2600 | |
| 1966 | Divisors | brute force dfs and similar implementation number theory | Statement | E | Codeforces Round 256 (Div. 2) {448} | PROGRAMMING | Codeforces Round #256 — Разбор | 2500 | |
| 2620 | Jzzhu and Apples | constructive algorithms number theory | Statement | C | Codeforces Round 257 (Div. 1) {449} | PROGRAMMING | Codeforces Round #257 Editorial | 2500 | |
| 341 | Jzzhu and Squares | dp math number theory | Statement | E | Codeforces Round 257 (Div. 1) {449} | PROGRAMMING | Codeforces Round #257 Editorial | 2900 | |
| 4741 | Devu and Flowers | bitmasks combinatorics number theory | Statement | E | Codeforces Round 258 (Div. 2) {451} | PROGRAMMING | Codeforces Round #258 Editorial | 2400 | |
| 18866 | Fedya and Maths | math number theory | Statement | B | Codeforces Round 260 (Div. 2) {456} | PROGRAMMING | Codeforces Round #260 — Editorial | 1200 | |
| 6024 | Pashmak and Graph | dp sortings | Statement | E | Codeforces Round 261 (Div. 2) {459} | PROGRAMMING | Codeforces Round #261 Editorial | 2100 | |
| 13515 | Little Dima and Equation | brute force implementation math number theory | Statement | B | Codeforces Round 262 (Div. 2) {460} | PROGRAMMING | 13465 | 1500 | |
| 1058 | Little Victor and Set | brute force constructive algorithms math | Statement | D | Codeforces Round 262 (Div. 2) {460} | PROGRAMMING | 13465 | 2500 | |
| 1784 | Caisa and Tree | brute force dfs and similar math number theory trees | Statement | E | Codeforces Round 264 (Div. 2) {463} | PROGRAMMING | CF 264 Div 2 Tutorial | 2400 | |
| 71979 | Design Tutorial: Learn from Math | math number theory | Statement | A | Codeforces Round 270 {472} | PROGRAMMING | Editorial | 900 | |
| 12264 | Ant colony | data structures math number theory | Statement | F | Codeforces Round 271 (Div. 2) {474} | PROGRAMMING | Codeforces Round #271 (Div. 2) Editorial | 2200 | |
| 25069 | Counterexample | brute force implementation math number theory | Statement | A | Codeforces Round 275 (Div. 2) {483} | PROGRAMMING | Codeforces Round #275 Editorial | 1100 | |
| 3159 | Prefix Product Sequence | constructive algorithms math number theory | Statement | C | Codeforces Round 278 (Div. 1) {487} | PROGRAMMING | Tutorial | 2600 | |
| 9526 | Hacking Cypher | brute force math number theory strings | Statement | C | Codeforces Round 279 (Div. 2) {490} | PROGRAMMING | Codeforces Round #279 (Div. 2) Editorial | 1700 | |
| 2333 | Chocolate | brute force dfs and similar math meet-in-the-middle number theory | Statement | D | Codeforces Round 279 (Div. 2) {490} | PROGRAMMING | Codeforces Round #279 (Div. 2) Editorial | 1900 | |
| 8432 | Modular Equations | math number theory | Statement | B | Codeforces Round 282 (Div. 2) {495} | PROGRAMMING | Tutorial | 1600 | |
| 1272 | Traffic Jams in the Land | data structures dp number theory | Statement | D | Codeforces Round 284 (Div. 1) {498} | PROGRAMMING | Codeforces Round #284 Editorial | 2400 | |
| 4325 | Array and Operations | flows graph matchings number theory | Statement | C | Codeforces Round 284 (Div. 1) {498} | PROGRAMMING | Codeforces Round #284 Editorial | 2400 | |
| 45533 | Lecture | implementation strings | Statement | B | Codeforces Round 284 (Div. 2) {499} | PROGRAMMING | 15353 | 1000 | |
| 312 | New Year Running | number theory trees | Statement | G | Good Bye 2014 {500} | PROGRAMMING | Tutorial 2 | 3000 | |
| 7804 | Drazil and His Happy Friends | brute force dsu meet-in-the-middle number theory | Statement | B | Codeforces Round 292 (Div. 2) {515} | PROGRAMMING | Codeforces Round #292 Editorial | 1400 | |
| 660 | Drazil and His Happy Friends | math number theory | Statement | E | Codeforces Round 292 (Div. 1) {516} | PROGRAMMING | 16468 | 3000 | |
| 20827 | A and B and Team Training | greedy implementation math number theory | Statement | C | Codeforces Round 294 (Div. 2) {519} | PROGRAMMING | Editorial | 1300 | |
| 2134 | Pluses everywhere | combinatorics dp math number theory | Statement | E | Codeforces Round 295 (Div. 2) {520} | PROGRAMMING | Codeforces Round #295 Editorial (now with bonuses!) | 2500 | |
| 541 | Superhero's Job | dfs and similar dp hashing math number theory | Statement | D | VK Cup 2015 - Round 3 (unofficial online mirror, Div. 1 only) {542} | PROGRAMMING | 17697 | 2600 | |
| 14073 | Soldier and Number Game | constructive algorithms dp math number theory | Statement | D | Codeforces Round 304 (Div. 2) {546} | PROGRAMMING | Codeforces Round #304 (Div.2) editorial | 1700 | |
| 3522 | Mike and Foam | bitmasks combinatorics dp math number theory | Statement | C | Codeforces Round 305 (Div. 1) {547} | PROGRAMMING | Codeforces Round #305 Editorial | 2700 | |
| 2139 | GukiZ and Binary Operations | combinatorics implementation math matrices number theory | Statement | D | Codeforces Round 307 (Div. 2) {551} | PROGRAMMING | Tutorial | 2400 | |
| 5889 | Vanya and Scales | brute force dp greedy math meet-in-the-middle number theory | Statement | C | Codeforces Round 308 (Div. 2) {552} | PROGRAMMING | Codeforces #308 (Div. 2) Editorial | 1800 | |
| 2431 | Vitaly and Cycle | combinatorics dfs and similar graphs math | Statement | D | Codeforces Round 311 (Div. 2) {557} | PROGRAMMING | Codeforces Round #311 (Div.2) Editorial | 2300 | |
| 8331 | Gerald and Giant Chess | combinatorics dp math number theory | Statement | C | Codeforces Round 313 (Div. 1) {559} | PROGRAMMING | Codeforces Round 313 — Extended editoral | 2500 | |
| 4348 | Clique in the Divisibility Graph | dp math number theory | Statement | F | VK Cup 2015 - Finals, online mirror {566} | PROGRAMMING | Editorial for VK Cup 2015 — Finals | 1600 | |
| 5424 | Primes or Palindromes? | brute force implementation math number theory | Statement | A | Codeforces Round 315 (Div. 1) {568} | PROGRAMMING | Codeforces Round #315 Editorial | 1700 | |
| 2398 | Symmetric and Transitive | combinatorics dp math | Statement | B | Codeforces Round 315 (Div. 1) {568} | PROGRAMMING | Codeforces Round #315 Editorial | 2100 | |
| 18626 | 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 | |
| 1893 | Bots | combinatorics number theory | Statement | H | Bubble Cup 8 - Finals [Online Mirror] {575} | PROGRAMMING | Bubble Cup finals 2015 Results and Editorial | 1800 | |
| 16122 | Vasya and Petya's Game | math number theory | Statement | A | Codeforces Round 319 (Div. 1) {576} | PROGRAMMING | Editorial Codeforces Round #319 | 1500 | |
| 46173 | Multiplication Table | implementation number theory | Statement | A | Codeforces Round 319 (Div. 2) {577} | PROGRAMMING | Editorial Codeforces Round #319 | 1100 | |
| 8398 | GCD Table | constructive algorithms greedy number theory | Statement | A | Codeforces Round 323 (Div. 1) {582} | PROGRAMMING | Codeforces Round #323 Editorial | 1700 | |
| 817 | Superior Periodic Subarrays | number theory | Statement | C | Codeforces Round 323 (Div. 1) {582} | PROGRAMMING | Codeforces Round #323 Editorial | 2900 | |
| 830 | Number of Binominal Coefficients | dp math number theory | Statement | D | Codeforces Round 323 (Div. 1) {582} | PROGRAMMING | Codeforces Round #323 Editorial | 3100 | |
| 11310 | Dima and Lisa | brute force math number theory | Statement | D | Codeforces Round 324 (Div. 2) {584} | PROGRAMMING | Tutorial | 1700 | |
| 1083 | Alice, Bob, Oranges and Apples | number theory | Statement | C | Codeforces Round 325 (Div. 1) {585} | PROGRAMMING | Разбор Codeforces Round #325 | 2400 | |
| 1281 | Present for Vitalik the Philatelist | combinatorics math number theory | Statement | E | Codeforces Round 325 (Div. 1) {585} | PROGRAMMING | Разбор Codeforces Round #325 | 2800 | |
| 2117 | REQ | data structures number theory | Statement | D | Codeforces Round 330 (Div. 1) {594} | PROGRAMMING | Codeforces Round #330 (Div.1 + Div.2) Editorial | 2500 | |
| 2744 | Moodular Arithmetic | combinatorics dfs and similar dsu math number theory | Statement | B | Codeforces Round 334 (Div. 1) {603} | PROGRAMMING | Codeforces Round #334 Editorial | 2000 | |
| 4350 | Multipliers | math number theory | Statement | D | Codeforces Round 338 (Div. 2) {615} | PROGRAMMING | Codeforces Round #338 (Div. 2) editorial | 1900 | |
| 3668 | Sum of Remainders | implementation math number theory | Statement | E | Educational Codeforces Round 5 {616} | PROGRAMMING | Editorial of Educational Codeforces Round 5 | 2200 | |
| 6394 | Wet Shark and Flowers | combinatorics math number theory probabilities | Statement | C | Codeforces Round 341 (Div. 2) {621} | PROGRAMMING | 1700 | ||
| 2416 | Array GCD | dp greedy number theory | Statement | B | AIM Tech Round (Div. 1) {623} | PROGRAMMING | AIM Tech Round Tutorial | 2400 | |
| 4629 | Block Towers | brute force greedy math number theory | Statement | C | 8VC Venture Cup 2016 - Elimination Round {626} | PROGRAMMING | 23522 | 1600 | |
| 12908 | Divisibility | math number theory | Statement | J | Experimental Educational Round: VolBIT Formulas Blitz {630} | PROGRAMMING | Разбор задач Experimental Educational Round: VolBIT Formulas Blitz | 1200 | |
| 9699 | Game | games math | Statement | R | Experimental Educational Round: VolBIT Formulas Blitz {630} | PROGRAMMING | Разбор задач Experimental Educational Round: VolBIT Formulas Blitz | 1300 | |
| 6463 | Indivisibility | math number theory | Statement | K | Experimental Educational Round: VolBIT Formulas Blitz {630} | PROGRAMMING | Разбор задач Experimental Educational Round: VolBIT Formulas Blitz | 1700 | |
| 96439 | Again Twenty Five! | number theory | Statement | A | Experimental Educational Round: VolBIT Formulas Blitz {630} | PROGRAMMING | Разбор задач Experimental Educational Round: VolBIT Formulas Blitz | 800 | |
| 4684 | Longest Subsequence | brute force math number theory | Statement | D | Educational Codeforces Round 9 {632} | PROGRAMMING | 43493 | 2200 | |
| 14956 | Ebony and Ivory | brute force math number theory | Statement | A | Manthan, Codefest 16 {633} | PROGRAMMING | Manthan, Codefest 16: Editorials | 1200 | |
| 7315 | A Trivial Problem | brute force constructive algorithms math number theory | Statement | B | Manthan, Codefest 16 {633} | PROGRAMMING | Manthan, Codefest 16: Editorials | 1300 | |
| 932 | Yash And Trees | bitmasks data structures dfs and similar math number theory | Statement | G | Manthan, Codefest 16 {633} | PROGRAMMING | Manthan, Codefest 16: Editorials | 2700 | |
| 1601 | 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 | |
| 1037 | Cowslip Collections | combinatorics math number theory | Statement | F | CROC 2016 - Elimination Round {645} | PROGRAMMING | Editorial for CROC 2016 Elimination Round | 2500 | |
| 2240 | Table Compression | dfs and similar dp dsu graphs greedy | Statement | C | Codeforces Round 345 (Div. 1) {650} | PROGRAMMING | Codeforces Round #345: editorial | 2300 | |
| 768 | Move by Prime | combinatorics math number theory | Statement | G | IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} | PROGRAMMING | IndiaHacks Finals 2016 — Editorial | 3000 | |
| 1344 | Fence Divercity | combinatorics dp number theory | Statement | G | Codeforces Round 346 (Div. 2) {659} | PROGRAMMING | Editorial for Codeforces Round #346 (Div. 2) | 2500 | |
| 10584 | Co-prime Array | greedy implementation math number theory | Statement | A | Educational Codeforces Round 11 {660} | PROGRAMMING | Editorial of Educational Codeforces Round 11 | 1300 | |
| 22315 | Complicated GCD | math number theory | Statement | A | Codeforces Round 347 (Div. 2) {664} | PROGRAMMING | Editorial for CROC 2016 Finals and Codeforces Round #347 | 900 | |
| 4225 | Simple Subset | constructive algorithms greedy number theory | Statement | D | Educational Codeforces Round 12 {665} | PROGRAMMING | Editorial | 2000 | |
| 836 | Four Divisors | dp math number theory | Statement | F | Educational Codeforces Round 12 {665} | PROGRAMMING | Editorial | 2600 | |
| 838 | Ultimate Weirdness of an Array | data structures number theory | Statement | C | Codeforces Round 352 (Div. 1) {671} | PROGRAMMING | Codeforces Round #352 Editorial | 2700 | |
| 11215 | Joty and Chocolate | implementation math number theory | Statement | C | Educational Codeforces Round 13 {678} | PROGRAMMING | Editorial | 1600 | |
| 5474 | Iterated Linear Function | math number theory | Statement | D | Educational Codeforces Round 13 {678} | PROGRAMMING | Editorial | 1800 | |
| 24256 | Alyona and Numbers | constructive algorithms math number theory | Statement | A | Codeforces Round 358 (Div. 2) {682} | PROGRAMMING | 45491 | 1200 | |
| 7026 | Remainders Game | chinese remainder theorem math number theory | Statement | B | Codeforces Round 360 (Div. 1) {687} | PROGRAMMING | Codeforces Round #360 Editorial [+ Challenges!] | 1900 | |
| 1478 | Couple Cover | brute force dp number theory | Statement | F | Educational Codeforces Round 14 {691} | PROGRAMMING | Editorial of Educational Codeforces Round 14 | 2300 | |
| 554 | Coprime Permutation | combinatorics number theory | Statement | F | Codeforces Round 363 (Div. 1) {698} | PROGRAMMING | Solution | 3000 | |
| 696 | Mishka and Divisors | dp number theory | Statement | E | Codeforces Round 365 (Div. 2) {703} | PROGRAMMING | Codeforces Round #365 (Div. 2) Editorial | 2900 | |
| 562 | Black Widow | dp graphs implementation math | Statement | C | Codeforces Round 366 (Div. 1) {704} | PROGRAMMING | Tutorial | 2800 | |
| 13572 | Pythagorean Triples | math number theory | Statement | C | Codeforces Round 368 (Div. 2) {707} | PROGRAMMING | 46662 | 1500 | |
| 1434 | ZS and The Birthday Paradox | math number theory probabilities | Statement | E | Codeforces Round 369 (Div. 2) {711} | PROGRAMMING | 46830 | 2400 | |
| 473 | Festival Organization | math number theory | Statement | A | Bubble Cup 9 - Finals [Online Mirror] {717} | PROGRAMMING | Tutorial | 3000 | |
| 639 | 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 | |
| 2290 | 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 | |
| 1595 | Xor-matic Number of the Graph | bitmasks graphs math number theory trees | Statement | G | Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} | PROGRAMMING | Tutorial | 2600 | |
| 3171 | Video Cards | brute force data structures implementation math number theory | Statement | F | Codeforces Round 376 (Div. 2) {731} | PROGRAMMING | 47840 | 1900 | |
| 8779 | Urbanization | greedy number theory sortings | Statement | B | Codeforces Round 382 (Div. 2) {735} | PROGRAMMING | Codeforces Round #382 Editorial | 1200 | |
| 16211 | Taxes | math number theory | Statement | D | Codeforces Round 382 (Div. 2) {735} | PROGRAMMING | Codeforces Round #382 Editorial | 1600 | |
| 53283 | 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 | |
| 10134 | Arpa’s obvious problem and Mehrdad’s terrible solution | brute force math number theory | Statement | B | Codeforces Round 383 (Div. 2) {742} | PROGRAMMING | Test data | 1500 | |
| 13579 | Vladik and fractions | brute force constructive algorithms math number theory | Statement | C | Codeforces Round 384 (Div. 2) {743} | PROGRAMMING | Codeforces Round #384 Editorial | 1500 | |
| 58033 | Bachgold Problem | greedy implementation math number theory | Statement | A | Codeforces Round 388 (Div. 2) {749} | PROGRAMMING | Tutorial | 700 | |
| 1140 | PolandBall and Many Other Balls | combinatorics divide and conquer dp fft math number theory | Statement | G | 8VC Venture Cup 2017 - Elimination Round {755} | PROGRAMMING | 8VC Venture Cup 2017 — Elimination Round [Editorial] | 3100 | |
| 20138 | PolandBall and Hypothesis | brute force graphs math number theory | Statement | A | 8VC Venture Cup 2017 - Elimination Round {755} | PROGRAMMING | 8VC Venture Cup 2017 — Elimination Round [Editorial] | 900 | |
| 229 | Long number | expression parsing math number theory | Statement | F | 8VC Venture Cup 2017 - Final Round {756} | PROGRAMMING | 8VC Venture Cup 2017 — Final Round and Codeforces Round #393 Editorial | 3200 | |
| 11571 | Bash's Big Day | greedy math number theory | Statement | B | Codecraft-17 and Codeforces Round 391 (Div. 1 + Div. 2, combined) {757} | PROGRAMMING | CodeCraft-17 and Codeforces Round #391 (Div. 1 + Div. 2, combined) Editorial | 1400 | |
| 1627 | Bash Plays with Functions | brute force combinatorics dp number theory | Statement | E | Codecraft-17 and Codeforces Round 391 (Div. 1 + Div. 2, combined) {757} | PROGRAMMING | CodeCraft-17 and Codeforces Round #391 (Div. 1 + Div. 2, combined) Editorial | 2400 | |
| 10779 | Blown Garland | brute force implementation number theory | Statement | B | Codeforces Round 392 (Div. 2) {758} | PROGRAMMING | Codeforces Round #392 (Div. 2) Editorial | 1200 | |
| 760 | Geometrical Progression | brute force math number theory | Statement | F | Codeforces Round 392 (Div. 2) {758} | PROGRAMMING | Codeforces Round #392 (Div. 2) Editorial | 2500 | |
| 26746 | k-th divisor | math number theory | Statement | A | Educational Codeforces Round 17 {762} | PROGRAMMING | Tutorial | 1500 | |
| 816 | Timofey and remoduling | brute force implementation math number theory | Statement | C | Codeforces Round 395 (Div. 1) {763} | PROGRAMMING | Codeforces Round #395 [Editorial] | 2500 | |
| 119 | Math, math everywhere | brute force dp math meet-in-the-middle number theory | Statement | G | Codeforces Round 397 by Kaspersky Lab and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {765} | PROGRAMMING | Codeforces Round #397 Editorial | 2800 | |
| 38886 | Mahmoud and a Triangle | constructive algorithms geometry greedy math number theory sortings | Statement | B | Codeforces Round 396 (Div. 2) {766} | PROGRAMMING | Codeforces round #396 editorial | 1100 | |
| 1155 | Barrels and boxes | brute force combinatorics math number theory probabilities | Statement | F | Divide by Zero 2017 and Codeforces Round 399 (Div. 1 + Div. 2, combined) {768} | PROGRAMMING | Editorial Divide by Zero and Codeforces Round #399 (Div. 1+2, combined) | 2300 | |
| 1488 | Vulnerable Kerbals | constructive algorithms dp graphs math number theory | Statement | C | VK Cup 2017 - Round 2 {772} | PROGRAMMING | VK Cup Round 2 + Codeforces Round #409 Tutorial | 2400 | |
| 280 | Test Data Generation | combinatorics divide and conquer dp fft math number theory | Statement | F | VK Cup 2017 - Round 3 {773} | PROGRAMMING | VK Cup 2017 Round 3 + Codeforces Round #412 -- Tutorial | 3400 | |
| 282 | Big Number and Remainder | *special math number theory | Statement | E | VK Cup 2017 - Wild Card Round 1 {774} | PROGRAMMING | VK Cup 2017 — Уайлд-кард раунд 1 — Разбор | 2400 | |
| 198 | Pens And Days Of Week | *special binary search number theory | Statement | F | VK Cup 2017 - Wild Card Round 1 {774} | PROGRAMMING | VK Cup 2017 — Уайлд-кард раунд 1 — Разбор | 2600 | |
| 244 | Perfectionist Arkadiy | *special number theory | Statement | G | VK Cup 2017 - Wild Card Round 1 {774} | PROGRAMMING | VK Cup 2017 — Уайлд-кард раунд 1 — Разбор | 2900 | |
| 26576 | Sherlock and his girlfriend | constructive algorithms number theory | Statement | B | ICM Technex 2017 and Codeforces Round 400 (Div. 1 + Div. 2, combined) {776} | PROGRAMMING | ICM Technex 2017 and Codeforces Round #400 (Div. 1 + Div. 2, combined) Editorial | 1200 | |
| 2527 | The Holmes Children | math number theory | Statement | E | ICM Technex 2017 and Codeforces Round 400 (Div. 1 + Div. 2, combined) {776} | PROGRAMMING | ICM Technex 2017 and Codeforces Round #400 (Div. 1 + Div. 2, combined) Editorial | 2100 | |
| 3871 | Anton and School - 2 | combinatorics dp math number theory | Statement | D | Codeforces Round 404 (Div. 2) {785} | PROGRAMMING | Editorial | 2200 | |
| 12260 | The Monster | brute force math number theory | Statement | A | Codeforces Round 406 (Div. 2) {787} | PROGRAMMING | Codeforces Round #406 Editorial | 1300 | |
| 5092 | Divide by Three | dp greedy math number theory | Statement | C | Educational Codeforces Round 18 {792} | PROGRAMMING | Educational Codeforces Round 18 - Editorial | 2000 | |
| 1299 | Colored Balls | greedy math number theory | Statement | E | Educational Codeforces Round 18 {792} | PROGRAMMING | Educational Codeforces Round 18 - Editorial | 2400 | |
| 20531 | k-Factorization | implementation math number theory | Statement | A | Educational Codeforces Round 19 {797} | PROGRAMMING | 51588 | 1100 | |
| 6437 | Mike and gcd problem | dp greedy number theory | Statement | C | Codeforces Round 410 (Div. 2) {798} | PROGRAMMING | Codeforces Round #410 (Div. 2) Editorial | 1700 | |
| 4952 | Coprime Subsequences | bitmasks combinatorics number theory | Statement | F | Educational Codeforces Round 20 {803} | PROGRAMMING | 51768 | 2100 | |
| 221 | Fake bullions | combinatorics dfs and similar dp graphs number theory | Statement | F | Codeforces Round 411 (Div. 1) {804} | PROGRAMMING | Codeforces Round #411 Editorial | 3400 | |
| 991 | Surprise me! | divide and conquer math number theory trees | Statement | E | Codeforces Round 415 (Div. 1) {809} | PROGRAMMING | 52099 | 3000 | |
| 6946 | Treasure Hunt | implementation math number theory | Statement | A | Educational Codeforces Round 23 {817} | PROGRAMMING | 52638 | 1200 | |
| 2709 | Card Game Again | binary search data structures number theory two pointers | Statement | E | Educational Codeforces Round 24 {818} | PROGRAMMING | 52991 | 2000 | |
| 359 | Mister B and Astronomers | number theory | Statement | D | Codeforces Round 421 (Div. 1) {819} | PROGRAMMING | Codeforces Round #421 Editorial | 2900 | |
| 271 | Mister B and Beacons on Field | number theory | Statement | C | Codeforces Round 421 (Div. 1) {819} | PROGRAMMING | Codeforces Round #421 Editorial | 3000 | |
| 3298 | My pretty girl Noora | brute force dp greedy math number theory | Statement | D | Codeforces Round 422 (Div. 2) {822} | PROGRAMMING | Codeforces Round #422 (Div. 2) Editorial | 1800 | |
| 400 | Madness | constructive algorithms dfs and similar trees | Statement | F | Codeforces Round 422 (Div. 2) {822} | PROGRAMMING | Codeforces Round #422 (Div. 2) Editorial | 2700 | |
| 37410 | 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 | |
| 1345 | 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 | |
| 6600 | The Meaningless Game | math number theory | Statement | A | Codeforces Round 426 (Div. 1) {833} | PROGRAMMING | Codeforces Round #426 Editorial | 1700 | |
| 2187 | Vasya's Function | binary search implementation math | Statement | E | Educational Codeforces Round 26 {837} | PROGRAMMING | 53662 | 2200 | |
| 1197 | Airplane Arrangements | math number theory | Statement | D | IndiaHacks 2nd Elimination 2017 (unofficial, unrated mirror, ICPC rules) {838} | PROGRAMMING | 53736 | 2700 | |
| 3663 | Winter is here | combinatorics dp math number theory | Statement | D | Codeforces Round 428 (Div. 2) {839} | PROGRAMMING | Codeforces Round #428 editorial | 2200 | |
| 7574 | Leha and Function | combinatorics greedy math number theory sortings | Statement | A | Codeforces Round 429 (Div. 1) {840} | PROGRAMMING | Editorial | 1300 | |
| 3816 | Ilya And The Tree | dfs and similar graphs math number theory trees | Statement | C | Codeforces Round 430 (Div. 2) {842} | PROGRAMMING | Tutorial Codeforces Round #430 (Div. 2) | 2000 | |
| 2219 | 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 | |
| 667 | Product transformation | combinatorics math number theory | Statement | F | Bubble Cup X - Finals [Online Mirror] {852} | PROGRAMMING | Tutorial | 2300 | |
| 1646 | Set Theory | brute force constructive algorithms | Statement | A | Russian Code Cup 2017 - Finals [Unofficial Mirror, Div. 1 Only Recommended, Teams Allowed] {856} | PROGRAMMING | Tutorial | 1600 |