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< 1 2 3 4 5 6 7 ... 12 13 14 >Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 11203 | Commentary Boxes | implementation math | Statement | A | Educational Codeforces Round 45 (Rated for Div. 2) {990} | PROGRAMMING | Educational Codeforces Round 45 Editorial | 1000 | |
| 3724 | Bus Number | brute force combinatorics math | Statement | E | Codeforces Round 491 (Div. 2) {991} | PROGRAMMING | 60181 | 1800 | |
| 340 | Concise and clear | brute force greedy implementation math | Statement | F | Codeforces Round 491 (Div. 2) {991} | PROGRAMMING | 60181 | 2800 | |
| 4860 | Nastya and a Wardrobe | math | Statement | C | Codeforces Round 489 (Div. 2) {992} | PROGRAMMING | 60083 | 1700 | |
| 6747 | Nastya Studies Informatics | math number theory | Statement | B | Codeforces Round 489 (Div. 2) {992} | PROGRAMMING | 60083 | 1700 | |
| 1749 | Nastya and a Game | brute force implementation math | Statement | D | Codeforces Round 489 (Div. 2) {992} | PROGRAMMING | 60083 | 2100 | |
| 1766 | Nikita and Order Statistics | chinese remainder theorem fft math | Statement | E | Codeforces Round 488 by NEAR (Div. 1) {993} | PROGRAMMING | Codeforces Round #488 editorial | 2300 | |
| 7436 | Suit and Tie | greedy implementation math | Statement | B | Codeforces Round 492 (Div. 1) [Thanks, uDebug!] {995} | PROGRAMMING | Editorial for Codeforces Round #492 [Thanks u-Debug!] | 1500 | |
| 2049 | Leaving the Bar | brute force data structures geometry greedy math sortings | Statement | C | Codeforces Round 492 (Div. 1) [Thanks, uDebug!] {995} | PROGRAMMING | Editorial for Codeforces Round #492 [Thanks u-Debug!] | 2200 | |
| 897 | Game | math | Statement | D | Codeforces Round 492 (Div. 1) [Thanks, uDebug!] {995} | PROGRAMMING | Editorial for Codeforces Round #492 [Thanks u-Debug!] | 2400 | |
| 1603 | Cowmpany Cowmpensation | combinatorics dp math trees | Statement | F | Codeforces Round 492 (Div. 1) [Thanks, uDebug!] {995} | PROGRAMMING | Editorial for Codeforces Round #492 [Thanks u-Debug!] | 2700 | |
| 9889 | World Cup | binary search math | Statement | B | Codeforces Round 492 (Div. 2) [Thanks, uDebug!] {996} | PROGRAMMING | Editorial for Codeforces Round #492 [Thanks u-Debug!] | 1300 | |
| 8653 | Convert to Ones | brute force greedy implementation math | Statement | A | Codeforces Round 493 (Div. 1) {997} | PROGRAMMING | 60357 | 1500 | |
| 3135 | Roman Digits | brute force combinatorics dp greedy math | Statement | B | Codeforces Round 493 (Div. 1) {997} | PROGRAMMING | 60357 | 2000 | |
| 2170 | Sky Full of Stars | combinatorics math | Statement | C | Codeforces Round 493 (Div. 1) {997} | PROGRAMMING | 60357 | 2600 | |
| 11485 | Intense Heat | brute force implementation math | Statement | C | Codeforces Round 494 (Div. 3) {1003} | PROGRAMMING | 60417 | 1300 | |
| 9929 | Sonya and Exhibition | constructive algorithms greedy implementation math | Statement | B | Codeforces Round 495 (Div. 2) {1004} | PROGRAMMING | 60443 | 1400 | |
| 13039 | Reorder the Array | combinatorics data structures math sortings two pointers | Statement | A | Codeforces Round 497 (Div. 1) {1007} | PROGRAMMING | Editorial for Codeforces Round #497 by Skyglow | 1300 | |
| 1037 | Pave the Parallelepiped | bitmasks brute force combinatorics math number theory | Statement | B | Codeforces Round 497 (Div. 1) {1007} | PROGRAMMING | Editorial for Codeforces Round #497 by Skyglow | 2400 | |
| 6625 | Relatively Prime Graph | brute force constructive algorithms graphs greedy math | Statement | D | Educational Codeforces Round 47 (Rated for Div. 2) {1009} | PROGRAMMING | 60630 | 1700 | |
| 5537 | Annoying Present | greedy math | Statement | C | Educational Codeforces Round 47 (Rated for Div. 2) {1009} | PROGRAMMING | 60630 | 1700 | |
| 3317 | Intercity Travelling | combinatorics math probabilities | Statement | E | Educational Codeforces Round 47 (Rated for Div. 2) {1009} | PROGRAMMING | 60630 | 1900 | |
| 8991 | Fly | binary search math | Statement | A | Codeforces Round 499 (Div. 1) {1010} | PROGRAMMING | 60851 | 1500 | |
| 6673 | Photo of The Sky | brute force implementation math sortings | Statement | A | Codeforces Round 500 (Div. 1) [based on EJOI] {1012} | PROGRAMMING | 60920 | 1500 | |
| 396 | Cycle sort | dsu math | Statement | E | Codeforces Round 500 (Div. 1) [based on EJOI] {1012} | PROGRAMMING | 60920 | 3100 | |
| 11696 | Piles With Stones | math | Statement | A | Codeforces Round 500 (Div. 2) [based on EJOI] {1013} | PROGRAMMING | Codeforces Round #500 (based on EJOI 2018) — Editorial | 800 | |
| 4983 | Vasya And The Matrix | constructive algorithms flows math | Statement | D | Educational Codeforces Round 48 (Rated for Div. 2) {1016} | PROGRAMMING | Разбор Educational Codeforces Round 48 | 1800 | |
| 315 | Appropriate Team | bitmasks math number theory | Statement | G | Educational Codeforces Round 48 (Rated for Div. 2) {1016} | PROGRAMMING | Разбор Educational Codeforces Round 48 | 2800 | |
| 15671 | Death Note | greedy implementation math | Statement | A | Educational Codeforces Round 48 (Rated for Div. 2) {1016} | PROGRAMMING | Разбор Educational Codeforces Round 48 | 900 | |
| 9618 | The Bits | implementation math | Statement | B | Codeforces Round 502 (in memory of Leopoldo Taravilse, Div. 1 + Div. 2) {1017} | PROGRAMMING | Разбор (англ.) | 1200 | |
| 943 | The Neutral Zone | brute force math | Statement | F | Codeforces Round 502 (in memory of Leopoldo Taravilse, Div. 1 + Div. 2) {1017} | PROGRAMMING | Разбор (англ.) | 2500 | |
| 21564 | The Rank | implementation | Statement | A | Codeforces Round 502 (in memory of Leopoldo Taravilse, Div. 1 + Div. 2) {1017} | PROGRAMMING | Разбор (англ.) | 700 | |
| 9449 | New Building for SIS | math | Statement | A | Codeforces Round 503 (by SIS, Div. 2) {1020} | PROGRAMMING | Codeforces Round #503 (based on SIS olympiad) — Editorial | 1100 | |
| 11639 | Pair of Toys | math | Statement | B | Codeforces Round 504 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1023} | PROGRAMMING | Codeforces Round 504 Editorial | 1100 | |
| 8497 | Weakened Common Divisor | brute force greedy number theory | Statement | B | Codeforces Round 505 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1025} | PROGRAMMING | Codeforces Round #505 Editorial | 1600 | |
| 4113 | Recovering BST | brute force dp math number theory trees | Statement | D | Codeforces Round 505 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1025} | PROGRAMMING | Codeforces Round #505 Editorial | 2000 | |
| 863 | Company Acquisitions | constructive algorithms math | Statement | G | Codeforces Round 505 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1025} | PROGRAMMING | Codeforces Round #505 Editorial | 3100 | |
| 8737 | Numbers on the Chessboard | implementation math | Statement | B | Educational Codeforces Round 49 (Rated for Div. 2) {1027} | PROGRAMMING | Educational Codeforces Round 49 Editorial | 1300 | |
| 2360 | Inverse Coloring | combinatorics dp math | Statement | E | Educational Codeforces Round 49 (Rated for Div. 2) {1027} | PROGRAMMING | Educational Codeforces Round 49 Editorial | 2100 | |
| 359 | X-mouse in the Campus | bitmasks math number theory | Statement | G | Educational Codeforces Round 49 (Rated for Div. 2) {1027} | PROGRAMMING | Educational Codeforces Round 49 Editorial | 2800 | |
| 10213 | Unnatural Conditions | constructive algorithms math | Statement | B | AIM Tech Round 5 (rated, Div. 1 + Div. 2) {1028} | PROGRAMMING | 61493 | 1300 | |
| 564 | Make Square | math | Statement | H | AIM Tech Round 5 (rated, Div. 1 + Div. 2) {1028} | PROGRAMMING | 61493 | 2900 | |
| 18407 | Creating the Contest | dp greedy math | Statement | B | Codeforces Round 506 (Div. 3) {1029} | PROGRAMMING | Codeforces Round #506 (Div. 3) Editorial | 1200 | |
| 8238 | Maximal Intersection | greedy math sortings | Statement | C | Codeforces Round 506 (Div. 3) {1029} | PROGRAMMING | Codeforces Round #506 (Div. 3) Editorial | 1600 | |
| 2749 | Multicolored Markers | binary search brute force math number theory | Statement | F | Codeforces Round 506 (Div. 3) {1029} | PROGRAMMING | Codeforces Round #506 (Div. 3) Editorial | 2100 | |
| 4226 | Concatenated Multiples | implementation math | Statement | D | Codeforces Round 506 (Div. 3) {1029} | PROGRAMMING | Codeforces Round #506 (Div. 3) Editorial | 2100 | |
| 4058 | Curiosity Has No Limits | Statement | B | Technocup 2019 - Elimination Round 2 {1031} | PROGRAMMING | Codeforces Round #517 and Technocup 2019 Elimination Round 2 Editorial | 1500 | ||
| 310 | Familiar Operations | brute force graphs math | Statement | F | Technocup 2019 - Elimination Round 2 {1031} | PROGRAMMING | Codeforces Round #517 and Technocup 2019 Elimination Round 2 Editorial | 2700 | |
| 13392 | Golden Plate | implementation math | Statement | A | Technocup 2019 - Elimination Round 2 {1031} | PROGRAMMING | Codeforces Round #517 and Technocup 2019 Elimination Round 2 Editorial | 700 | |
| 1864 | The Unbearable Lightness of Weights | dp math | Statement | E | Technocup 2019 - Elimination Round 3 {1032} | PROGRAMMING | Codeforces Round #522 and Technocup 2019 Elimination Round 3 Editorial | 2300 | |
| 11894 | Square Difference | math number theory | Statement | B | Lyft Level 5 Challenge 2018 - Elimination Round {1033} | PROGRAMMING | The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial | 1100 | |
| 2606 | Divisors | interactive math number theory | Statement | D | Lyft Level 5 Challenge 2018 - Elimination Round {1033} | PROGRAMMING | The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial | 2000 | |
| 461 | Boolean Computer | bitmasks brute force fft math | Statement | F | Lyft Level 5 Challenge 2018 - Elimination Round {1033} | PROGRAMMING | The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial | 2800 | |
| 748 | Little C Loves 3 III | bitmasks dp math | Statement | E | Codeforces Round 511 (Div. 1) {1034} | PROGRAMMING | Codeforces Round #511 Editorial | 3200 | |
| 10575 | Function Height | math | Statement | A | Educational Codeforces Round 50 (Rated for Div. 2) {1036} | PROGRAMMING | 61727 | 1000 | |
| 5960 | Diagonal Walking v.2 | math | Statement | B | Educational Codeforces Round 50 (Rated for Div. 2) {1036} | PROGRAMMING | 61727 | 1600 | |
| 1851 | Relatively Prime Powers | combinatorics math number theory | Statement | F | Educational Codeforces Round 50 (Rated for Div. 2) {1036} | PROGRAMMING | 61727 | 2400 | |
| 11815 | Packets | constructive algorithms greedy math | Statement | A | Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} | PROGRAMMING | Tutorial | 1300 | |
| 1268 | Maximum Reduction | combinatorics data structures math | Statement | F | Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} | PROGRAMMING | Tutorial | 2400 | |
| 14685 | Non-Coprime Partition | constructive algorithms math | Statement | B | Codeforces Round 508 (Div. 2) {1038} | PROGRAMMING | Tutorial | 1100 | |
| 1094 | Maximum Matching | bitmasks brute force dfs and similar dp graphs | Statement | E | Codeforces Round 508 (Div. 2) {1038} | PROGRAMMING | Tutorial | 2400 | |
| 1487 | Network Safety | dfs and similar dsu graphs math sortings | Statement | C | Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} | PROGRAMMING | 61668 | 2300 | |
| 851 | Timetable | constructive algorithms data structures greedy math | Statement | A | Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} | PROGRAMMING | 61668 | 2400 | |
| 7473 | Shashlik Cooking | dp greedy math | Statement | B | Codeforces Round 507 (Div. 2, based on Olympiad of Metropolises) {1040} | PROGRAMMING | Codeforces Round #507 (based on Olympiad of Metropolises) — Editorial | 1300 | |
| 15009 | Buying a TV Set | math | Statement | B | Codeforces Round 509 (Div. 2) {1041} | PROGRAMMING | Codeforces Round #509 (Div. 2) Editorial | 1100 | |
| 1614 | Ray in the tube | data structures divide and conquer dp math | Statement | F | Codeforces Round 509 (Div. 2) {1041} | PROGRAMMING | Codeforces Round #509 (Div. 2) Editorial | 2400 | |
| 4966 | Array Product | constructive algorithms greedy math | Statement | C | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 1700 | |
| 2077 | Vasya and Magic Matrix | dp math probabilities | Statement | E | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 2300 | |
| 4757 | Mysterious Crime | brute force combinatorics math meet-in-the-middle two pointers | Statement | D | Codeforces Round 519 by Botan Investments {1043} | PROGRAMMING | Codeforces Round #519 Editorial | 1700 | |
| 3458 | Train Hard, Win Easy | constructive algorithms greedy math sortings | Statement | E | Codeforces Round 519 by Botan Investments {1043} | PROGRAMMING | Codeforces Round #519 Editorial | 1900 | |
| 2981 | Make It One | bitmasks combinatorics dp math number theory shortest paths | Statement | F | Codeforces Round 519 by Botan Investments {1043} | PROGRAMMING | Codeforces Round #519 Editorial | 2500 | |
| 11272 | Elections | implementation math | Statement | A | Codeforces Round 519 by Botan Investments {1043} | PROGRAMMING | Codeforces Round #519 Editorial | 800 | |
| 856 | Interstellar battle | math probabilities trees | Statement | D | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | Tutorial (PDF) | 2600 | |
| 439 | Self-exploration | math | Statement | H | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | E | 2700 | |
| 113 | Shady Lady | geometry math | Statement | F | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | E | 3500 | |
| 21213 | Little C Loves 3 I | math | Statement | A | Codeforces Round 511 (Div. 2) {1047} | PROGRAMMING | Codeforces Round #511 Editorial | 800 | |
| 18764 | Cover Points | geometry math | Statement | B | Codeforces Round 511 (Div. 2) {1047} | PROGRAMMING | Codeforces Round #511 Editorial | 900 | |
| 18779 | Relatively Prime Pairs | greedy math number theory | Statement | B | Educational Codeforces Round 51 (Rated for Div. 2) {1051} | PROGRAMMING | Educational Codeforces Round 51 Editorial | 1000 | |
| 9868 | Vasya and Multisets | brute force dp greedy implementation math | Statement | C | Educational Codeforces Round 51 (Rated for Div. 2) {1051} | PROGRAMMING | Educational Codeforces Round 51 Editorial | 1400 | |
| 514 | Chips Puzzle | constructive algorithms implementation math | Statement | E | Mail.Ru Cup 2018 Round 1 {1054} | PROGRAMMING | Editorial | 2400 | |
| 449 | New Road Network | constructive algorithms greedy math | Statement | G | Mail.Ru Cup 2018 Round 1 {1054} | PROGRAMMING | Editorial | 2900 | |
| 211 | Epic Convolution | chinese remainder theorem fft math number theory | Statement | H | Mail.Ru Cup 2018 Round 1 {1054} | PROGRAMMING | Editorial | 3400 | |
| 2055 | Lucky Days | math number theory | Statement | C | Mail.Ru Cup 2018 Round 2 {1055} | PROGRAMMING | Mail.Ru Cup 2018 Round 2 — analysis | 1900 | |
| 4544 | Divide Candies | math number theory | Statement | B | Mail.Ru Cup 2018 Round 3 {1056} | PROGRAMMING | Mail.Ru Cup 2018 Round 3 Editorial | 1600 | |
| 703 | Write The Contest | binary search dp math | Statement | F | Mail.Ru Cup 2018 Round 3 {1056} | PROGRAMMING | Mail.Ru Cup 2018 Round 3 Editorial | 2400 | |
| 7528 | Sequence Transformation | constructive algorithms math | Statement | C | Codeforces Round 514 (Div. 2) {1059} | PROGRAMMING | Codeforces Round #514 (Div. 2) Editorial | 1500 | |
| 3874 | Social Circles | greedy math | Statement | D | Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) {1060} | PROGRAMMING | User editorial for Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) | 1900 | |
| 10690 | Multiplicity | data structures dp implementation math number theory | Statement | C | Codeforces Round 523 (Div. 2) {1061} | PROGRAMMING | Tutorial (en) | 1700 | |
| 23998 | Coins | greedy implementation math | Statement | A | Codeforces Round 523 (Div. 2) {1061} | PROGRAMMING | Tutorial (en) | 800 | |
| 5946 | Banh-mi | greedy implementation math | Statement | C | Codeforces Round 520 (Div. 2) {1062} | PROGRAMMING | Tutorial | 1600 | |
| 9823 | Math | greedy math number theory | Statement | B | Codeforces Round 520 (Div. 2) {1062} | PROGRAMMING | Tutorial | 1600 | |
| 4164 | Fun with Integers | dfs and similar graphs implementation math | Statement | D | Codeforces Round 520 (Div. 2) {1062} | PROGRAMMING | Tutorial | 1800 | |
| 472 | Candies for Children | brute force math | Statement | D | Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} | PROGRAMMING | Editorial | 2800 | |
| 401 | Lasers and Mirrors | constructive algorithms math | Statement | E | Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} | PROGRAMMING | Editorial | 3000 | |
| 7934 | Equations of Mathematical Magic | math | Statement | B | Codeforces Round 516 (Div. 2, by Moscow Team Olympiad) {1064} | PROGRAMMING | Codeforces Round #516 (by Moscow Team Olympiad) — Editorial | 1200 | |
| 25073 | Make a triangle! | brute force geometry math | Statement | A | Codeforces Round 516 (Div. 2, by Moscow Team Olympiad) {1064} | PROGRAMMING | Codeforces Round #516 (by Moscow Team Olympiad) — Editorial | 700 | |
| 15257 | Vasya and Chocolate | implementation math | Statement | A | Educational Codeforces Round 52 (Rated for Div. 2) {1065} | PROGRAMMING | Educational Codeforces Round 52 Editorial | 800 | |
| 15409 | Vova and Train | math | Statement | A | Codeforces Round 515 (Div. 3) {1066} | PROGRAMMING | 62419 | 1100 | |
| 6556 | Binary Numbers AND Sum | data structures implementation math | Statement | E | Codeforces Round 515 (Div. 3) {1066} | PROGRAMMING | 62419 | 1700 | |
| 552 | Random Forest Rank | dp graph matchings math trees | Statement | E | Codeforces Round 518 (Div. 1) [Thanks, Mail.Ru!] {1067} | PROGRAMMING | Tutorial | 2800 | |
| 490 | Computer Game | dp greedy math probabilities | Statement | D | Codeforces Round 518 (Div. 1) [Thanks, Mail.Ru!] {1067} | PROGRAMMING | Tutorial | 2800 | |
| 12967 | LCM | math number theory | Statement | B | Codeforces Round 518 (Div. 2) [Thanks, Mail.Ru!] {1068} | PROGRAMMING | E | 1200 | |
| 7254 | Birthday | math | Statement | A | Codeforces Round 518 (Div. 2) [Thanks, Mail.Ru!] {1068} | PROGRAMMING | E | 1300 | |
| 11213 | Vasya and Books | implementation math | Statement | B | Educational Codeforces Round 53 (Rated for Div. 2) {1073} | PROGRAMMING | 62742 | 1100 | |
| 3540 | Segment Sum | bitmasks combinatorics dp math | Statement | E | Educational Codeforces Round 53 (Rated for Div. 2) {1073} | PROGRAMMING | 62742 | 2300 | |
| 9129 | The King's Race | implementation math | Statement | A | Lyft Level 5 Challenge 2018 - Final Round (Open Div. 2) {1075} | PROGRAMMING | E | 900 | |
| 14555 | Divisor Subtraction | implementation math number theory | Statement | B | Educational Codeforces Round 54 (Rated for Div. 2) {1076} | PROGRAMMING | E | 1200 | |
| 13390 | Meme Problem | binary search math | Statement | C | Educational Codeforces Round 54 (Rated for Div. 2) {1076} | PROGRAMMING | E | 1300 | |
| 32204 | Frog Jumping | math | Statement | A | Codeforces Round 521 (Div. 3) {1077} | PROGRAMMING | Codeforces Round #521 (Div. 3) Editorial | 700 | |
| 1664 | Olya and magical square | constructive algorithms implementation math | Statement | D | Codeforces Round 524 (Div. 2) {1080} | PROGRAMMING | Codeforces Round #524 (Div. 2) Editorial | 2000 | |
| 19158 | Petya and Origami | math | Statement | A | Codeforces Round 524 (Div. 2) {1080} | PROGRAMMING | Codeforces Round #524 (Div. 2) Editorial | 700 | |
| 12613 | Margarite and the best present | math | Statement | B | Codeforces Round 524 (Div. 2) {1080} | PROGRAMMING | Codeforces Round #524 (Div. 2) Editorial | 900 | |
| 8419 | Colorful Bricks | combinatorics dp math | Statement | C | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 1600 | |
| 2814 | Missing Numbers | binary search constructive algorithms greedy math number theory | Statement | E | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 1900 | |
| 433 | Mergesort Strikes Back | math probabilities | Statement | G | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 3000 | |
| 13265 | Definite Game | constructive algorithms math | Statement | A | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 800 | |
| 9261 | Vasya and Book | implementation math | Statement | A | Educational Codeforces Round 55 (Rated for Div. 2) {1082} | PROGRAMMING | 63544 | 1200 | |
| 10076 | Div Times Mod | math | Statement | B | Technocup 2019 - Elimination Round 4 {1085} | PROGRAMMING | Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial | 1200 | |
| 5642 | Connect Three | implementation math | Statement | C | Technocup 2019 - Elimination Round 4 {1085} | PROGRAMMING | Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial | 1600 | |
| 314 | Forest Fires | math | Statement | F | Codeforces Round 528 (Div. 1, based on Technocup 2019 Elimination Round 4) {1086} | PROGRAMMING | Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial | 3400 | |
| 8512 | Ehab and a 2-operation task | constructive algorithms greedy math | Statement | C | Codeforces Round 525 (Div. 2) {1088} | PROGRAMMING | Codeforces round #525 editorial | 1400 | |
| 1614 | Ehab and a component choosing problem | dp greedy math trees | Statement | E | Codeforces Round 525 (Div. 2) {1088} | PROGRAMMING | Codeforces round #525 editorial | 2400 | |
| 3219 | Guest Student | math | Statement | G | 2018-2019 ICPC, NEERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1089} | PROGRAMMING | T | 1600 | |
| 2148 | Fractions | math | Statement | F | 2018-2019 ICPC, NEERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1089} | PROGRAMMING | T | 2000 | |
| 1419 | Berland University | greedy math | Statement | L | 2018-2019 Russia Open High School Programming Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1090} | PROGRAMMING | 2100 | ||
| 1197 | Right Expansion Of The Mind | math | Statement | K | 2018-2019 Russia Open High School Programming Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1090} | PROGRAMMING | 2100 | ||
| 600 | Two Prefixes | strings | Statement | J | 2018-2019 Russia Open High School Programming Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1090} | PROGRAMMING | ru-olymp-team-russia-2018-presentation.pdf | 2700 | |
| 10540 | New Year and the Sphere Transmission | math number theory | Statement | C | Good Bye 2018 {1091} | PROGRAMMING | Editorial | 1400 | |
| 7465 | New Year and the Permutation Concatenation | combinatorics dp math | Statement | D | Good Bye 2018 {1091} | PROGRAMMING | Editorial | 1700 | |
| 1086 | New Year and the Acquaintance Estimation | binary search data structures graphs greedy implementation math sortings | Statement | E | Good Bye 2018 {1091} | PROGRAMMING | Editorial | 2400 | |
| 227 | New Year and the Factorisation Collaboration | interactive math number theory | Statement | G | Good Bye 2018 {1091} | PROGRAMMING | Editorial | 3100 | |
| 18554 | New Year and the Christmas Ornament | brute force implementation math | Statement | A | Good Bye 2018 {1091} | PROGRAMMING | Editorial | 900 | |
| 5641 | Great Vova Wall (Version 1) | greedy implementation math | Statement | D1 | Codeforces Round 527 (Div. 3) {1092} | PROGRAMMING | Codeforces Round #527 (Div. 3) Editorial | 2100 | |
| 18340 | Dice Rolling | math | Statement | A | Educational Codeforces Round 56 (Rated for Div. 2) {1093} | PROGRAMMING | 63877 | 700 | |
| 11670 | Substring Removal | combinatorics math strings | Statement | B | Educational Codeforces Round 57 (Rated for Div. 2) {1096} | PROGRAMMING | Разбор Educational Codeforces Round 57 | 1400 | |
| 2057 | Inversion Expectation | dp math probabilities | Statement | F | Educational Codeforces Round 57 (Rated for Div. 2) {1096} | PROGRAMMING | Разбор Educational Codeforces Round 57 | 2300 | |
| 1277 | The Top Scorer | combinatorics dp math probabilities | Statement | E | Educational Codeforces Round 57 (Rated for Div. 2) {1096} | PROGRAMMING | Разбор Educational Codeforces Round 57 | 2600 | |
| 19600 | Find Divisible | greedy implementation math | Statement | A | Educational Codeforces Round 57 (Rated for Div. 2) {1096} | PROGRAMMING | Разбор Educational Codeforces Round 57 | 800 | |
| 3163 | Makoto and a Blackboard | dp math number theory probabilities | Statement | D | Hello 2019 {1097} | PROGRAMMING | 64310 | 2200 | |
| 139 | Mateusz and an Infinite Sequence | bitmasks brute force dp strings | Statement | H | Hello 2019 {1097} | PROGRAMMING | 64310 | 3000 | |
| 1796 | Nice table | brute force constructive algorithms greedy math | Statement | B | Codeforces Round 530 (Div. 1) {1098} | PROGRAMMING | 64331 | 2300 | |
| 273 | Fedya the Potter | binary search implementation math number theory | Statement | E | Codeforces Round 530 (Div. 1) {1098} | PROGRAMMING | 64331 | 3400 | |
| 11472 | Squares and Segments | binary search constructive algorithms math | Statement | B | Codeforces Round 530 (Div. 2) {1099} | PROGRAMMING | E | 1100 | |
| 10858 | NN and the Optical Illusion | binary search geometry math | Statement | C | Codeforces Round 532 (Div. 2) {1100} | PROGRAMMING | Unofficial Tutorial | 1300 | |
| 3657 | Ivan and Burgers | data structures divide and conquer greedy math | Statement | F | Codeforces Round 532 (Div. 2) {1100} | PROGRAMMING | Unofficial Tutorial | 2600 | |
| 18793 | Minimum Integer | math | Statement | A | Educational Codeforces Round 58 (Rated for Div. 2) {1101} | PROGRAMMING | 64483 | 1100 | |
| 2185 | (Zero XOR Subset)-less | math matrices | Statement | G | Educational Codeforces Round 58 (Rated for Div. 2) {1101} | PROGRAMMING | 64483 | 2400 | |
| 26580 | Integer Sequence Dividing | math | Statement | A | Codeforces Round 531 (Div. 3) {1102} | PROGRAMMING | 64439 | 1000 | |
| 953 | Johnny Solving | constructive algorithms dfs and similar graphs math | Statement | C | Codeforces Round 534 (Div. 1) {1103} | PROGRAMMING | Codeforces Round #534 — Editorial | 2800 | |
| 281 | Radix sum | fft math number theory | Statement | E | Codeforces Round 534 (Div. 1) {1103} | PROGRAMMING | Codeforces Round #534 — Editorial | 3300 | |
| 16768 | Game with string | data structures implementation math | Statement | B | Codeforces Round 534 (Div. 2) {1104} | PROGRAMMING | Codeforces Round #534 — Editorial | 1300 | |
| 15891 | Splitting into digits | constructive algorithms implementation math | Statement | A | Codeforces Round 534 (Div. 2) {1104} | PROGRAMMING | Codeforces Round #534 — Editorial | 800 | |
| 11335 | Ayoub and Lost Array | combinatorics dp math | Statement | C | Codeforces Round 533 (Div. 2) {1105} | PROGRAMMING | Tutorial | 1500 | |
| 15738 | Lunar New Year and Number Division | greedy implementation math sortings | Statement | C | Codeforces Round 536 (Div. 2) {1106} | PROGRAMMING | Tutorial | 1000 | |
| 2813 | Lunar New Year and Red Envelopes | data structures dp | Statement | E | Codeforces Round 536 (Div. 2) {1106} | PROGRAMMING | Tutorial | 2100 | |
| 1179 | Lunar New Year and a Recursive Sequence | math matrices number theory | Statement | F | Codeforces Round 536 (Div. 2) {1106} | PROGRAMMING | Tutorial | 2400 | |
| 17697 | Digital root | math number theory | Statement | B | Educational Codeforces Round 59 (Rated for Div. 2) {1107} | PROGRAMMING | Educational Codeforces Round 59 Editorial | 1100 | |
| 3900 | Compression | dp implementation math number theory | Statement | D | Educational Codeforces Round 59 (Rated for Div. 2) {1107} | PROGRAMMING | Educational Codeforces Round 59 Editorial | 1800 | |
| 25136 | Divisors of Two Integers | brute force greedy math number theory | Statement | B | Codeforces Round 535 (Div. 3) {1108} | PROGRAMMING | 64751 | 1100 | |
| 12640 | Nice Garland | brute force greedy math | Statement | C | Codeforces Round 535 (Div. 3) {1108} | PROGRAMMING | 64751 | 1300 | |
| 1499 | Sasha and Interesting Fact from Graph Theory | brute force combinatorics dp math trees | Statement | D | Codeforces Round 539 (Div. 1) {1109} | PROGRAMMING | Codeforces Round #539 Editorial | 2600 | |
| 598 | Sasha and a Very Easy Test | data structures number theory | Statement | E | Codeforces Round 539 (Div. 1) {1109} | PROGRAMMING | Codeforces Round #539 Editorial | 2700 | |
| 15980 | Parity | math | Statement | A | Codeforces Global Round 1 {1110} | PROGRAMMING | The Editorial of the First Codeforces Global Round | 1000 | |
| 9995 | Meaningless Operations | constructive algorithms math number theory | Statement | C | Codeforces Global Round 1 {1110} | PROGRAMMING | The Editorial of the First Codeforces Global Round | 1500 | |
| 4699 | Magic Stones | constructive algorithms math sortings | Statement | E | Codeforces Global Round 1 {1110} | PROGRAMMING | The Editorial of the First Codeforces Global Round | 2200 | |
| 6508 | Average Superhero Gang Power | brute force implementation math | Statement | B | CodeCraft-19 and Codeforces Round 537 (Div. 2) {1111} | PROGRAMMING | CodeCraft-19 and Codeforces Round #537 (Div. 2) Editorial | 1600 | |
| 6878 | Creative Snap | binary search brute force divide and conquer math | Statement | C | CodeCraft-19 and Codeforces Round 537 (Div. 2) {1111} | PROGRAMMING | CodeCraft-19 and Codeforces Round #537 (Div. 2) Editorial | 1700 | |
| 1139 | Destroy the Colony | combinatorics dp math | Statement | D | CodeCraft-19 and Codeforces Round 537 (Div. 2) {1111} | PROGRAMMING | CodeCraft-19 and Codeforces Round #537 (Div. 2) Editorial | 2500 | |
| 18297 | Sasha and His Trip | dp greedy math | Statement | A | Codeforces Round 539 (Div. 2) {1113} | PROGRAMMING | Codeforces Round #539 Editorial | 900 | |
| 7823 | Trailing Loves (or L'oeufs?) | brute force implementation math number theory | Statement | C | Codeforces Round 538 (Div. 2) {1114} | PROGRAMMING | Codeforces Round #538 (Div. 2) Editorial | 1700 | |
| 2419 | Please, another Queries on Array? | bitmasks data structures divide and conquer math number theory | Statement | F | Codeforces Round 538 (Div. 2) {1114} | PROGRAMMING | Codeforces Round #538 (Div. 2) Editorial | 2500 | |
| 15715 | Emotes | greedy math sortings | Statement | B | Educational Codeforces Round 60 (Rated for Div. 2) {1117} | PROGRAMMING | 65365 | 1000 | |
| 11441 | Best Subsegment | implementation math | Statement | A | Educational Codeforces Round 60 (Rated for Div. 2) {1117} | PROGRAMMING | 65365 | 1100 | |
| 5168 | Magic Gems | dp math matrices | Statement | D | Educational Codeforces Round 60 (Rated for Div. 2) {1117} | PROGRAMMING | 65365 | 2000 | |
| 1635 | Decypher the String | bitmasks chinese remainder theorem constructive algorithms interactive math | Statement | E | Educational Codeforces Round 60 (Rated for Div. 2) {1117} | PROGRAMMING | 65365 | 2200 | |
| 21535 | Water Buying | math | Statement | A | Codeforces Round 540 (Div. 3) {1118} | PROGRAMMING | 65396 | 800 | |
| 7174 | Ramesses and Corner Inversion | constructive algorithms greedy implementation math | Statement | C | Codeforces Global Round 2 {1119} | PROGRAMMING | Codeforces Global Round 2 Editorial | 1500 | |
| 791 | Triple | fft math | Statement | H | Codeforces Global Round 2 {1119} | PROGRAMMING | Codeforces Global Round 2 Editorial | 3100 | |
| 480 | Once in a casino | constructive algorithms greedy implementation math | Statement | B | Codeforces Round 543 (Div. 1, based on Technocup 2019 Final Round) {1120} | PROGRAMMING | Разбор задач финала Технокубка 2019 и Codeforces Round #543 | 2700 | |
| 12802 | Sea Battle | math | Statement | A | Codeforces Round 541 (Div. 2) {1131} | PROGRAMMING | Codeforces Round #541 Editorial | 800 | |
| 14317 | Preparation for International Women's Day | math number theory | Statement | B | Codeforces Round 544 (Div. 3) {1133} | PROGRAMMING | Codeforces Round #544 (Div. 3) Editorial | 1300 | |
| 16348 | Zero Quantity Maximization | hashing math number theory | Statement | D | Codeforces Round 544 (Div. 3) {1133} | PROGRAMMING | Codeforces Round #544 (Div. 3) Editorial | 1500 | |
| 12267 | Nastya Is Playing Computer Games | constructive algorithms math | Statement | B | Codeforces Round 546 (Div. 2) {1136} | PROGRAMMING | Editorial of Round #546(Div.2) | 1000 | |
| 4199 | Circus | brute force greedy math strings | Statement | B | Codeforces Round 545 (Div. 2) {1138} | PROGRAMMING | Codeforces Round #545 – Editorial | 1700 | |
| 16570 | Edgy Trees | dfs and similar dsu graphs math trees | Statement | C | Codeforces Round 548 (Div. 2) {1139} | PROGRAMMING | Codeforces Round #548 Editorial | 1500 | |
| 2694 | Steps to One | dp math number theory probabilities | Statement | D | Codeforces Round 548 (Div. 2) {1139} | PROGRAMMING | Codeforces Round #548 Editorial | 2300 | |
| 13145 | Minimum Triangulation | dp greedy math | Statement | D | Educational Codeforces Round 62 (Rated for Div. 2) {1140} | PROGRAMMING | Educational Codeforces Round 62 Editorial | 1200 | |
| 38442 | Game 23 | implementation math | Statement | A | Codeforces Round 547 (Div. 3) {1141} | PROGRAMMING | 66062 | 1000 | |
| 12267 | Polycarp Restores Permutation | math | Statement | C | Codeforces Round 547 (Div. 3) {1141} | PROGRAMMING | 66062 | 1400 | |
| 7098 | Superhero Battle | math | Statement | E | Codeforces Round 547 (Div. 3) {1141} | PROGRAMMING | 66062 | 1700 | |
| 3578 | The Beatles | brute force math | Statement | A | Codeforces Round 549 (Div. 1) {1142} | PROGRAMMING | Codeforces Round #549 Editorial | 1800 | |
| 3718 | Lynyrd Skynyrd | data structures dfs and similar dp math trees | Statement | B | Codeforces Round 549 (Div. 1) {1142} | PROGRAMMING | Codeforces Round #549 Editorial | 2300 | |
| 11530 | Nirvana | brute force math number theory | Statement | B | Codeforces Round 549 (Div. 2) {1143} | PROGRAMMING | Codeforces Round #549 Editorial | 1300 | |
| 4415 | Median String | bitmasks math number theory strings | Statement | E | Codeforces Round 550 (Div. 3) {1144} | PROGRAMMING | 66307 | 1900 | |
| 1202 | Frog Jumping | dfs and similar math number theory | Statement | D | Forethought Future Cup - Elimination Round {1146} | PROGRAMMING | 66639 | 2100 | |
| 1819 | Earth Wind and Fire | constructive algorithms greedy math sortings two pointers | Statement | E | Codeforces Global Round 3 {1148} | PROGRAMMING | Codeforces Global Round 3 Editorial | 2300 | |
| 387 | Gold Experience | constructive algorithms graphs math number theory probabilities | Statement | G | Codeforces Global Round 3 {1148} | PROGRAMMING | Codeforces Global Round 3 Editorial | 3100 | |
| 17778 | Prefix Sum Primes | constructive algorithms greedy math number theory | Statement | A | Codeforces Round 556 (Div. 1) {1149} | PROGRAMMING | 66783 | 1300 | |
| 9053 | Stas and the Queue at the Buffet | greedy math sortings | Statement | D | Codeforces Round 553 (Div. 2) {1151} | PROGRAMMING | Codeforces Round #553 (Div. 2) Editorial | 1500 | |
| 5597 | Problem for Nazar | constructive algorithms math | Statement | C | Codeforces Round 553 (Div. 2) {1151} | PROGRAMMING | Codeforces Round #553 (Div. 2) Editorial | 1700 | |
| 3762 | Number of Components | combinatorics data structures dp math | Statement | E | Codeforces Round 553 (Div. 2) {1151} | PROGRAMMING | Codeforces Round #553 (Div. 2) Editorial | 2100 | |
| 9302 | Neko Performs Cat Furrier Transform | bitmasks constructive algorithms dfs and similar math | Statement | B | Codeforces Round 554 (Div. 2) {1152} | PROGRAMMING | T | 1300 | |
| 7063 | Neko does Maths | brute force math number theory | Statement | C | Codeforces Round 554 (Div. 2) {1152} | PROGRAMMING | T | 1800 | |
| 16195 | Neko Finds Grapes | greedy implementation math | Statement | A | Codeforces Round 554 (Div. 2) {1152} | PROGRAMMING | T | 800 | |
| 12096 | Serval and Bus | brute force math | Statement | A | Codeforces Round 551 (Div. 2) {1153} | PROGRAMMING | Editorial | 1100 | |
| 7789 | Serval and Parenthesis Sequence | greedy strings | Statement | C | Codeforces Round 551 (Div. 2) {1153} | PROGRAMMING | Editorial | 1600 | |
| 5521 | Serval and Rooted Tree | binary search dfs and similar dp greedy trees | Statement | D | Codeforces Round 551 (Div. 2) {1153} | PROGRAMMING | Editorial | 1800 | |
| 929 | Serval and Bonus Problem | combinatorics dp math probabilities | Statement | F | Codeforces Round 551 (Div. 2) {1153} | PROGRAMMING | Editorial | 2800 | |
| 17630 | Make Them Equal | math | Statement | B | Codeforces Round 552 (Div. 3) {1154} | PROGRAMMING | Codeforces Round #552 (Div. 3) Editorial | 1200 | |
| 11527 | Gourmet Cat | implementation math | Statement | C | Codeforces Round 552 (Div. 3) {1154} | PROGRAMMING | Codeforces Round #552 (Div. 3) Editorial | 1400 | |
| 3247 | Minimum Possible LCM | brute force greedy math number theory | Statement | G | Codeforces Round 552 (Div. 3) {1154} | PROGRAMMING | Codeforces Round #552 (Div. 3) Editorial | 2400 | |
| 86707 | Restoring Three Numbers | math | Statement | A | Codeforces Round 552 (Div. 3) {1154} | PROGRAMMING | Codeforces Round #552 (Div. 3) Editorial | 600 | |
| 9714 | Alarm Clocks Everywhere | math number theory | Statement | C | Educational Codeforces Round 63 (Rated for Div. 2) {1155} | PROGRAMMING | 66687 | 1300 | |
| 1598 | Guess the Root | brute force interactive math | Statement | E | Educational Codeforces Round 63 (Rated for Div. 2) {1155} | PROGRAMMING | 66687 | 2200 | |
| 8634 | Inscribed Figures | geometry | Statement | A | Educational Codeforces Round 64 (Rated for Div. 2) {1156} | PROGRAMMING | 66827 | 1400 | |
| 1712 | Card Bag | dp math probabilities | Statement | F | Educational Codeforces Round 64 (Rated for Div. 2) {1156} | PROGRAMMING | 66827 | 2500 | |
| 3991 | N Problems During K Days | constructive algorithms greedy math | Statement | D | Codeforces Round 555 (Div. 3) {1157} | PROGRAMMING | 66737 | 2100 | |
| 8308 | The Party and Sweets | binary search constructive algorithms greedy implementation math sortings two pointers | Statement | A | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 1500 | |
| 2380 | The minimal unique substring | constructive algorithms math strings | Statement | B | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 2200 | |
| 2114 | Permutation recovery | constructive algorithms data structures dfs and similar graphs greedy math sortings | Statement | C | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 2300 | |
| 927 | Winding polygonal line | constructive algorithms geometry greedy math | Statement | D | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 2800 | |
| 193 | Strange device | binary search interactive math trees | Statement | E | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 3300 | |
| 502 | Density of subarrays | dp math | Statement | F | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 3400 | |
| 7844 | Expansion coefficient of the array | implementation math | Statement | B | Codeforces Round 559 (Div. 2) {1159} | PROGRAMMING | 66993 | 1300 | |
| 13399 | A pile of stones | implementation math | Statement | A | Codeforces Round 559 (Div. 2) {1159} | PROGRAMMING | 66993 | 800 | |
| 13846 | Eating Soup | greedy math | Statement | A | Codeforces Round 558 (Div. 2) {1163} | PROGRAMMING | 66943 | 1000 | |
| 3575 | Power Transmission (Easy Edition) | brute force geometry | Statement | C1 | Codeforces Round 558 (Div. 2) {1163} | PROGRAMMING | 66943 | 1900 | |
| 3947 | Power Transmission (Hard Edition) | data structures geometry implementation math | Statement | C2 | Codeforces Round 558 (Div. 2) {1163} | PROGRAMMING | 66943 | 2000 | |
| 1008 | Magical Permutation | bitmasks brute force constructive algorithms data structures graphs math | Statement | E | Codeforces Round 558 (Div. 2) {1163} | PROGRAMMING | 66943 | 2800 | |
| 14674 | Remainder | implementation math | Statement | A | Codeforces Round 560 (Div. 3) {1165} | PROGRAMMING | Codeforces Round #560 (Div. 3) Editorial | 1200 | |
| 19646 | Almost All Divisors | math number theory | Statement | D | Codeforces Round 560 (Div. 3) {1165} | PROGRAMMING | Codeforces Round #560 (Div. 3) Editorial | 1600 | |
| 9894 | Two Arrays and Sum of Functions | greedy math sortings | Statement | E | Codeforces Round 560 (Div. 3) {1165} | PROGRAMMING | Codeforces Round #560 (Div. 3) Editorial | 1800 | |
| 11913 | All the Vowels Please | constructive algorithms math number theory | Statement | B | Codeforces Round 561 (Div. 2) {1166} | PROGRAMMING | Codeforces Round #561 (Div. 2) Editorial | 1100 | |
| 3006 | The LCMs Must be Large | bitmasks brute force constructive algorithms math number theory | Statement | E | Codeforces Round 561 (Div. 2) {1166} | PROGRAMMING | Codeforces Round #561 (Div. 2) Editorial | 2000 | |
| 2282 | Cute Sequences | binary search brute force greedy math | Statement | D | Codeforces Round 561 (Div. 2) {1166} | PROGRAMMING | Codeforces Round #561 (Div. 2) Editorial | 2100 | |
| 16349 | Lost Numbers | brute force divide and conquer interactive math | Statement | B | Educational Codeforces Round 65 (Rated for Div. 2) {1167} | PROGRAMMING | 67058 | 1400 | |
| 1886 | Scalar Queries | combinatorics data structures math sortings | Statement | F | Educational Codeforces Round 65 (Rated for Div. 2) {1167} | PROGRAMMING | 67058 | 2300 | |
| 428 | Xor Permutations | constructive algorithms math | Statement | E | Codeforces Round 562 (Div. 1) {1168} | PROGRAMMING | Codeforces Round #562 — Editorial | 3100 | |
| 12675 | Circle Metro | implementation math | Statement | A | Codeforces Round 562 (Div. 2) {1169} | PROGRAMMING | Codeforces Round #562 — Editorial | 1000 | |
| 1560 | Three Integers Again | *special math | Statement | A | Kotlin Heroes: Episode 1 {1170} | PROGRAMMING | Kotlin Heroes Editorial | ||
| 1771 | Ehab and the Expected GCD Problem | combinatorics dp math number theory | Statement | E | Codeforces Round 563 (Div. 2) {1174} | PROGRAMMING | Codeforces round #563 editorial | 2500 | |
| 19709 | From Hero to Zero | implementation math | Statement | A | Educational Codeforces Round 66 (Rated for Div. 2) {1175} | PROGRAMMING | Editorial | 1000 | |
| 2643 | The Number of Subpermutations | brute force data structures divide and conquer hashing math | Statement | F | Educational Codeforces Round 66 (Rated for Div. 2) {1175} | PROGRAMMING | Editorial | 2600 | |
| 18287 | Merge it! | math | Statement | B | Codeforces Round 565 (Div. 3) {1176} | PROGRAMMING | 67598 | 1100 | |
| 13170 | Tiles | combinatorics greedy math | Statement | C | Codeforces Global Round 4 {1178} | PROGRAMMING | E | 1300 | |
| 7903 | Prime Graph | constructive algorithms greedy math number theory | Statement | D | Codeforces Global Round 4 {1178} | PROGRAMMING | E | 1600 | |
| 2444 | Serge and Dining Room | binary search data structures graph matchings greedy implementation math trees | Statement | C | Codeforces Round 569 (Div. 1) {1179} | PROGRAMMING | Editorial of Round #569 | 2400 | |
| 198 | Alesya and Discrete Math | divide and conquer interactive | Statement | E | Codeforces Round 569 (Div. 1) {1179} | PROGRAMMING | Editorial of Round #569 | 3200 | |
| 27385 | Alex and a Rhombus | dp implementation math | Statement | A | Codeforces Round 569 (Div. 2) {1180} | PROGRAMMING | Editorial of Round #569 | 800 | |
| 14774 | Chunga-Changa | greedy math | Statement | A | Codeforces Round 567 (Div. 2) {1181} | PROGRAMMING | Editorial of Codeforces Round #567 (based on All-Russian olympiad in the name of Keldysh) | 1000 |