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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 269 | Lucky Pair | combinatorics data structures implementation | Statement | D | Codeforces Round 104 (Div. 1) {145} | PROGRAMMING | Codeforces Round #104 - Editorial | 2800 | |
| 856 | Cow Tennis Tournament | combinatorics data structures math | Statement | E | Codeforces Round 174 (Div. 1) {283} | PROGRAMMING | Math Problems on Codeforces #174 | 2700 | |
| 4963 | Matrix | combinatorics data structures implementation | Statement | A | Codeforces Round 213 (Div. 1) {364} | PROGRAMMING | Codeforces Round #213 Editorial | 1800 | |
| 4862 | Vanya and Triangles | brute force combinatorics data structures geometry math sortings | Statement | D | Codeforces Round 308 (Div. 2) {552} | PROGRAMMING | Codeforces #308 (Div. 2) Editorial | 1900 | |
| 15084 | Modulo Sum | combinatorics data structures dp two pointers | Statement | B | Codeforces Round 319 (Div. 2) {577} | PROGRAMMING | Editorial Codeforces Round #319 | 1800 | |
| 1170 | Famil Door and Roads | combinatorics data structures dfs and similar dp probabilities trees | Statement | E | Codeforces Round 343 (Div. 2) {629} | PROGRAMMING | Editorial of Codeforces Round #343 (Div.2) | 2400 | |
| 2133 | Mike and Geometry Problem | combinatorics data structures dp geometry implementation | Statement | E | Codeforces Round 361 (Div. 2) {689} | PROGRAMMING | Tutorial | 2300 | |
| 751 | Karen and Cards | binary search combinatorics data structures geometry | Statement | D | Codeforces Round 419 (Div. 1) {815} | PROGRAMMING | Codeforces Round #419 Editorial | 2700 | |
| 2506 | High Cry | binary search bitmasks combinatorics data structures divide and conquer | Statement | D | Codeforces Round 441 (Div. 1, by Moscow Team Olympiad) {875} | PROGRAMMING | Codeforces Round #441. Editorial. | 2200 | |
| 293 | K Paths | combinatorics data structures dp fft math | Statement | H | Avito Code Challenge 2018 {981} | PROGRAMMING | Avito Code Challenge 2018 — разбор | 2900 | |
| 13099 | 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 | |
| 1826 | Order book | combinatorics data structures greedy | Statement | D | AIM Tech Round 5 (rated, Div. 1 + Div. 2) {1028} | PROGRAMMING | 61493 | 2100 | |
| 1273 | Maximum Reduction | combinatorics data structures math | Statement | F | Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} | PROGRAMMING | Tutorial | 2400 | |
| 711 | Beautiful Matrix | combinatorics data structures dp | Statement | G | Technocup 2019 - Elimination Round 4 {1085} | PROGRAMMING | Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial | 2600 | |
| 3790 | Number of Components | combinatorics data structures dp math | Statement | E | Codeforces Round 553 (Div. 2) {1151} | PROGRAMMING | Codeforces Round #553 (Div. 2) Editorial | 2100 | |
| 2933 | Range Deleting | binary search combinatorics data structures two pointers | Statement | E | Educational Codeforces Round 65 (Rated for Div. 2) {1167} | PROGRAMMING | 67058 | 2100 | |
| 1899 | Scalar Queries | combinatorics data structures math sortings | Statement | F | Educational Codeforces Round 65 (Rated for Div. 2) {1167} | PROGRAMMING | 67058 | 2300 | |
| 1860 | Culture Code | binary search combinatorics data structures dp shortest paths sortings | Statement | E | Educational Codeforces Round 69 (Rated for Div. 2) {1197} | PROGRAMMING | E | 2300 | |
| 1791 | Beautiful Rectangle | brute force combinatorics constructive algorithms data structures greedy math | Statement | C | Codeforces Round 606 (Div. 1, based on Technocup 2020 Elimination Round 4) {1276} | PROGRAMMING | Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial | 2300 | |
| 11486 | New Year and Ascent Sequence | binary search combinatorics data structures dp implementation sortings | Statement | B | Hello 2020 {1284} | PROGRAMMING | Hello 2020 Editorial | 1500 | |
| 2058 | AND Segments | bitmasks combinatorics data structures dp two pointers | Statement | F | Educational Codeforces Round 84 (Rated for Div. 2) {1327} | PROGRAMMING | Educational Codeforces Round 84 Editorial | 2500 | |
| 1165 | Mercenaries | bitmasks combinatorics data structures math two pointers | Statement | G | Educational Codeforces Round 94 (Rated for Div. 2) {1400} | PROGRAMMING | 81942 | ||
| 8375 | Rescue Nibel! | combinatorics data structures sortings | Statement | D | Codeforces Round 672 (Div. 2) {1420} | PROGRAMMING | 2000.0 | Editorial | |
| 5328 | Identify the Operations | brute force combinatorics data structures dsu greedy implementation | Statement | B | Codeforces Round 681 (Div. 1, based on VK Cup 2019-2020 - Final) {1442} | PROGRAMMING | 1000.0 | 84298 | |
| 6677 | Number of Simple Paths | combinatorics data structures dfs and similar dsu graphs trees | Statement | E | Codeforces Round 686 (Div. 3) {1454} | PROGRAMMING | Codeforces Round #686 (Div. 3) Editorial | ||
| 375 | Strange Permutation | binary search combinatorics data structures dp two pointers | Statement | E | Codeforces Round 694 (Div. 1) {1470} | PROGRAMMING | 2000.0 | 86464 | |
| 2341 | Copy or Prefix Sum | combinatorics data structures dp sortings | Statement | F | Codeforces Round 701 (Div. 2) {1485} | PROGRAMMING | 3000.0 | Editorial of Codeforces Round #701 (Div. 2) | 2400 |
| 812 | Pairs of Paths | combinatorics data structures trees | Statement | F | Codeforces Round 703 (Div. 2) {1486} | PROGRAMMING | 3000.0 | Codeforces Round #703 (Div. 2) Editorial | |
| 71 | Build From Suffixes | *special combinatorics data structures | Statement | H | Kotlin Heroes: Episode 6 {1488} | PROGRAMMING | 88522 | ||
| 12255 | Planar Reflections | brute force combinatorics data structures dp | Statement | C | CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} | PROGRAMMING | 1750.0 | CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial | |
| 2292 | MEX Tree | combinatorics constructive algorithms data structures dfs and similar math trees | Statement | D | Codeforces Round 721 (Div. 2) {1527} | PROGRAMMING | 2250.0 | Tutorial | 2400 |
| 1145 | Top-Notch Insertions | combinatorics data structures | Statement | D | Codeforces Round 740 (Div. 1, based on VK Cup 2021 - Final (Engine)) {1558} | PROGRAMMING | 2000.0 | Codeforces Round #740 Editorial | 2600 |
| 336 | Non-equal Neighbours | combinatorics data structures dp math | Statement | F | Codeforces Round 759 (Div. 2, based on Technocup 2022 Elimination Round 3) {1591} | PROGRAMMING | 3000.0 | Codeforces Round #759 (Div. 2, based on Technocup 2022 Elimination Round 3) Editorial | |
| 2506 | Staircases | brute force combinatorics data structures dfs and similar dp | Statement | E | Educational Codeforces Round 115 (Rated for Div. 2) {1598} | PROGRAMMING | 95890 | ||
| 19094 | Weird Sum | combinatorics data structures geometry math matrices sortings | Statement | A | Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} | PROGRAMMING | 500.0 | Codeforces Round #775 Editorial | |
| 3348 | Tyler and Strings | combinatorics data structures implementation strings | Statement | C | Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} | PROGRAMMING | 1500.0 | Codeforces Round #775 Editorial | |
| 1140 | Points | combinatorics data structures math matrices | Statement | F | Educational Codeforces Round 131 (Rated for Div. 2) {1701} | PROGRAMMING | Educational Codeforces Round 131 Editorial | ||
| 2467 | Mark and Professor Koro | binary search bitmasks combinatorics data structures greedy | Statement | E | Codeforces Round 807 (Div. 2) {1705} | PROGRAMMING | 2500.0 | Codeforces Round #807 (Div 2.) Editorial | |
| 1619 | LCM Sum (hard version) | combinatorics data structures math number theory two pointers | Statement | E2 | Codeforces Round 813 (Div. 2) {1712} | PROGRAMMING | 750.0 | Codeforces Round #813 (Div. 2) Editorial | |
| 10450 | Monoblock | brute force combinatorics data structures divide and conquer greedy implementation | Statement | C | Codeforces Round 816 (Div. 2) {1715} | PROGRAMMING | 1750.0 | Codeforces Round #816 (Div. 2) editorial | |
| 599 | Electrical Efficiency | combinatorics data structures dp number theory trees | Statement | E | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 773 | Maximums and Minimums | combinatorics combinatorics data structures number theory | Statement | E | Codeforces Round 823 (Div. 2) {1730} | PROGRAMMING | 2250.0 | Codeforces Round #823 — editorial | 2700 |
| 6852 | Meta-set | brute force combinatorics data structures hashing math | Statement | D | Codeforces Round 824 (Div. 2) {1735} | PROGRAMMING | 1750.0 | Codeforces Round #824 — editorial | |
| 1814 | Intersection and Union | combinatorics data structures dp math matrices | Statement | F | Educational Codeforces Round 137 (Rated for Div. 2) {1743} | PROGRAMMING | Educational Codeforces Round 137 Editorial | 2300 | |
| 615 | Segment Covering | brute force combinatorics constructive algorithms data structures trees | Statement | G | Polynomial Round 2022 (Div. 1 + Div. 2, Rated, Prizes!) {1774} | PROGRAMMING | 3250.0 | Polynomial Round 2022 (Div. 1 + Div. 2) Editorial | |
| 1921 | Three Chairs | bitmasks brute force combinatorics data structures number theory sortings | Statement | F | Codeforces Round 846 (Div. 2) {1780} | PROGRAMMING | 2000.0 | 111841 | |
| 567 | Prediction | combinatorics data structures dp | Statement | G | Educational Codeforces Round 145 (Rated for Div. 2) {1809} | PROGRAMMING | 114300 | ||
| 2145 | Vlad and the Nice Paths (hard version) | binary search combinatorics data structures dp math two pointers | Statement | G2 | Codeforces Round 863 (Div. 3) {1811} | PROGRAMMING | 114788 | ||
| 10289 | Ira and Flamenco | combinatorics data structures implementation sortings | Statement | F | Codeforces Round 874 (Div. 3) {1833} | PROGRAMMING | 116636 | ||
| 15567 | The Morning Star | combinatorics data structures geometry implementation math sortings | Statement | G | Codeforces Round 886 (Div. 4) {1850} | PROGRAMMING | Codeforces Round #886 (Div. 4) Editorial | ||
| 3077 | Guess Game | bitmasks combinatorics constructive algorithms data structures games math probabilities strings trees | Statement | E | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) {1864} | PROGRAMMING | 2000.0 | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Editorial | |
| 1835 | Light Bulbs (Hard Version) | combinatorics data structures dfs and similar dp dsu graphs hashing | Statement | G2 | Codeforces Round 916 (Div. 3) {1914} | PROGRAMMING | Codeforces Round 916 (Div. 3) Editorial | ||
| 2084 | Yet Another Inversions Problem | bitmasks combinatorics data structures math | Statement | D | Codeforces Round 917 (Div. 2) {1917} | PROGRAMMING | 2250.0 | Editorial of Codeforces Round 917 (Div. 2) | |
| 347 | Digital Patterns | combinatorics data structures implementation math | Statement | F | Codeforces Round 924 (Div. 2) {1928} | PROGRAMMING | 2750.0 | Codeforces Round 924 Editorial | |
| 31294 | Divisible Pairs | combinatorics data structures hashing math | Statement | D | Codeforces Round 925 (Div. 3) {1931} | PROGRAMMING | 125878 | ||
| 2247 | Fenwick Tree | bitmasks brute force combinatorics data structures dp math trees | Statement | C | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1250.0 | Tutorial | 2300 |
| 19130 | Beautiful Triple Pairs | combinatorics data structures | Statement | C | Codeforces Round 946 (Div. 3) {1974} | PROGRAMMING | Codeforces Round #946 (Div. 3) Editorial | 1400 | |
| 5835 | Invertible Bracket Sequences | binary search combinatorics data structures divide and conquer implementation two pointers | Statement | D | Educational Codeforces Round 166 (Rated for Div. 2) {1976} | PROGRAMMING | Educational Codeforces Round 166 Editorial | ||
| 1312 | Splittable Permutations | combinatorics data structures dfs and similar greedy math trees | Statement | E | Educational Codeforces Round 166 (Rated for Div. 2) {1976} | PROGRAMMING | Educational Codeforces Round 166 Editorial | ||
| 16316 | Photoshoot for Gorillas | combinatorics data structures greedy math | Statement | E | Codeforces Round 966 (Div. 3) {2000} | PROGRAMMING | 132689 | ||
| 1913 | The Endspeaker (Hard Version) | binary search combinatorics data structures dp greedy implementation two pointers | Statement | D2 | Codeforces Round 982 (Div. 2) {2027} | PROGRAMMING | 1000.0 | Codeforces Round #982 (Div. 2) Editorial | |
| 1979 | MEXimize the Score | brute force combinatorics data structures dp math | Statement | E | Codeforces Round 979 (Div. 2) {2030} | PROGRAMMING | 2000.0 | Codeforces Round 979 Editorial | |
| 485 | Alternative Platforms | combinatorics data structures fft math sortings | Statement | F | 2024-2025 ICPC, NERC, Southern and Volga Russian Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2038} | PROGRAMMING | 2500 | ||
| 300 | Narrower Passageway | combinatorics data structures | Statement | E | 2024-2025 ICPC Asia Jakarta Regional Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2045} | PROGRAMMING | raRzKDJLPHcUnqTcwvGznwEdKiDWjEkd.pdf | 2700 | |
| 1560 | Counting Is Not Fun (Easy Version) | combinatorics data structures dfs and similar dsu implementation math | Statement | F1 | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 1750.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 935 | Counting Is Not Fun (Hard Version) | combinatorics data structures dfs and similar dsu trees | Statement | F2 | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 1500.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 1486 | Mycraft Sand Sort | combinatorics data structures dsu | Statement | E | Codeforces Round 1005 (Div. 2) {2064} | PROGRAMMING | 2250.0 | Codeforces Round 1005 (Div. 2) Editorial | |
| 1998 | Bro Thinks He's Him | combinatorics data structures dp matrices | Statement | H | Codeforces Round 1003 (Div. 4) {2065} | PROGRAMMING | Video Tutorial | ||
| 617 | Another Folding Strip | combinatorics data structures divide and conquer dp math sortings | Statement | E | Codeforces Round 1008 (Div. 1) {2077} | PROGRAMMING | 2250.0 | Codeforces Round 1008 (Div. 1, Div. 2) Editorial | |
| 1471 | Looking at Towers (difficult version) | combinatorics data structures dp implementation | Statement | E2 | Educational Codeforces Round 182 (Rated for Div. 2) {2144} | PROGRAMMING | Educational Codeforces Round 182 Editorial | ||
| 492 | Chain Prefix Rank (Hard Version) | combinatorics data structures dp math | Statement | F2 | Codeforces Global Round 30 (Div. 1 + Div. 2) {2164} | PROGRAMMING | 1500.0 | Codeforces Global Round 30 Editorial | |
| 1142 | Jumping Man | combinatorics data structures dp trees | Statement | F | Hello 2026 {2183} | PROGRAMMING | 2750.0 | ||
| 5909 | Exquisite Array | combinatorics data structures dsu | Statement | E | Codeforces Round 1072 (Div. 3) {2184} | PROGRAMMING | Codeforces Round 1072 (Div. 3) Editorial | ||
| 95 | Sum of MEX | *special combinatorics data structures dp math | Statement | H | Kotlin Heroes: Episode 14 {2199} | PROGRAMMING | 151783 | ||
| 967 | Learning Binary Search | combinatorics divide and conquer dp | Statement | F | Nebius Round 2 (Codeforces Round 1088, Div. 1 + Div. 2) {2211} | PROGRAMMING | 3000.0 | Nebius Round 2 and Codeforces Round 1088 Editorial | |
| 252 | Amanojaku and Sequence (Hard Version) | combinatorics data structures implementation math | Statement | E2 | Codeforces Round 1098 (Div. 2) {2228} | PROGRAMMING | 1500.0 | Codeforces Round 1098 (Div. 2) Editorial | |
| 1561 | Deconstruction Tree | combinatorics data structures dp graphs trees | Statement | E | Spectral::Cup 2026 Round 2 (Codeforces Round 1100, Div. 1 + Div. 2) {2229} | PROGRAMMING | 2500.0 | Spectral::Cup 2026 Round 2 (Codeforces Round 1100, Div. 1 + Div. 2) Editorial |