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< 1 2Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 2506 | Star MST | combinatorics dp math | Statement | E | Educational Codeforces Round 125 (Rated for Div. 2) {1657} | PROGRAMMING | 101161 | ||
| 19556 | Marin and Anti-coprime Permutation | combinatorics math | Statement | B | Codeforces Round 779 (Div. 2) {1658} | PROGRAMMING | 1000.0 | Codeforces Round #779 (Div. 2) Editorial | |
| 816 | Centroid Probabilities | combinatorics dp fft math | Statement | E | Codeforces Round 783 (Div. 1) {1667} | PROGRAMMING | 2750.0 | Codeforces Round #783 Editorial | 3000 |
| 434 | Permutation Counting | brute force combinatorics dp fft math | Statement | F | Educational Codeforces Round 127 (Rated for Div. 2) {1671} | PROGRAMMING | 102181 | ||
| 3632 | Lost Arithmetic Progression | combinatorics implementation math number theory | Statement | D | Codeforces Round 785 (Div. 2) {1673} | PROGRAMMING | 2000.0 | Codeforces Round #785 (Div. 2) Editorial | |
| 807 | Power or XOR? | combinatorics math number theory | Statement | E | Codeforces Round 785 (Div. 2) {1673} | PROGRAMMING | 2750.0 | Codeforces Round #785 (Div. 2) Editorial | |
| 29528 | Dictionary | combinatorics math | Statement | B | Codeforces Round 786 (Div. 3) {1674} | PROGRAMMING | 102482 | ||
| 313 | Become Big For Me | combinatorics constructive algorithms math number theory | Statement | E | Codeforces Round 796 (Div. 1) {1687} | PROGRAMMING | 2000.0 | Editorial of Codeforces Round 796 | |
| 1139 | K-Set Tree | combinatorics dfs and similar dp math trees | Statement | F | CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} | PROGRAMMING | 2750.0 | Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2) | |
| 204 | Maximum Product? | brute force combinatorics dp greedy math two pointers | Statement | H | Codeforces Global Round 21 {1696} | PROGRAMMING | 4000.0 | Editorial of Codeforces Global Round 21 | |
| 4944 | Placing Jinas | combinatorics math | Statement | E | Codeforces Global Round 21 {1696} | PROGRAMMING | 2000.0 | Editorial of Codeforces Global Round 21 | |
| 10770 | The Third Problem | combinatorics math two pointers | Statement | C | Codeforces Round 804 (Div. 2) {1699} | PROGRAMMING | 1500.0 | Codeforces Round #804 (Div. 2) 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 | ||
| 239 | Game of AI (easy version) | combinatorics fft math | Statement | H1 | CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} | PROGRAMMING | 2250.0 | CodeTON Round 2 Editorial | |
| 112 | Game of AI (hard version) | combinatorics fft math | Statement | H2 | CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} | PROGRAMMING | 2750.0 | CodeTON Round 2 Editorial | |
| 7184 | Mark and Lightbulbs | combinatorics constructive algorithms math sortings | Statement | D | Codeforces Round 807 (Div. 2) {1705} | PROGRAMMING | 1750.0 | Codeforces Round #807 (Div 2.) Editorial | |
| 894 | Partial Virtual Trees | combinatorics dp math trees | Statement | D | Codeforces Round 808 (Div. 1) {1707} | PROGRAMMING | 1750.0 | 104930 | |
| 2467 | LCM Sum (easy version) | binary search brute force combinatorics math number theory two pointers | Statement | E1 | Codeforces Round 813 (Div. 2) {1712} | PROGRAMMING | 2000.0 | Codeforces Round #813 (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 | |
| 690 | Lost Array | bitmasks combinatorics constructive algorithms dp math | Statement | F | Codeforces Round 812 (Div. 2) {1713} | PROGRAMMING | 3000.0 | Codeforces Round #812 (Div. 2) Editorial | 2900 |
| 1384 | Bags with Balls | combinatorics math number theory | Statement | F | Educational Codeforces Round 133 (Rated for Div. 2) {1716} | PROGRAMMING | 105653 | ||
| 4888 | Madoka and The Corruption Scheme | combinatorics math | Statement | D | Codeforces Round 818 (Div. 2) {1717} | PROGRAMMING | 2000.0 | Codeforces Round #818 (Div. 2) Editorial. | 1900 |
| 1955 | Circular Mirror | binary search combinatorics math two pointers | Statement | C | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 1725 | Almost Perfect | combinatorics fft math | Statement | E | Codeforces Round 819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 {1726} | PROGRAMMING | 2250.0 | Codeforces Round #819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 Editorial | |
| 857 | Function Sum | brute force combinatorics dp fft math | Statement | F | Codeforces Round 841 (Div. 2) and Divide by Zero 2022 {1731} | PROGRAMMING | 2750.0 | Codeforces Round #841 (Div. 2) and Divide By Zero 2022 Editorial | |
| 6846 | Meta-set | brute force combinatorics data structures hashing math | Statement | D | Codeforces Round 824 (Div. 2) {1735} | PROGRAMMING | 1750.0 | Codeforces Round #824 — editorial | |
| 1807 | Balance Addicts | combinatorics dp math two pointers | Statement | E | Codeforces Global Round 22 {1738} | PROGRAMMING | 2500.0 | Editorial of Codeforces Global Round <strong>22</strong> | |
| 1077 | Conditional Mix | combinatorics dp math | Statement | F | Codeforces Round 831 (Div. 1 + Div. 2) {1740} | PROGRAMMING | 2500.0 | Tutorial | 2600 |
| 1813 | 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 | |
| 304 | Antifibonacci Cut | bitmasks combinatorics dp math | Statement | G | Educational Codeforces Round 137 (Rated for Div. 2) {1743} | PROGRAMMING | Educational Codeforces Round 137 Editorial | 3000 | |
| 663 | List Generation | combinatorics math | Statement | E | Codeforces Round 832 (Div. 2) {1747} | PROGRAMMING | 2500.0 | Codeforces Round #832 (Div. 2) Editorial | |
| 7454 | Count GCD | bitmasks combinatorics dp math number theory | Statement | D | CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!) {1750} | PROGRAMMING | 1750.0 | CodeTON Round 3 (Div. 1 + Div. 2) Editorial | |
| 2791 | Carry Bit | bitmasks brute force combinatorics dp math | Statement | D | Pinely Round 1 (Div. 1 + Div. 2) {1761} | PROGRAMMING | 1750.0 | Pinely Round 1 (Div. 1 + Div. 2) Editorial | |
| 103 | Anti-median (Hard Version) | combinatorics dp math | Statement | F2 | Pinely Round 1 (Div. 1 + Div. 2) {1761} | PROGRAMMING | 2000.0 | Pinely Round 1 (Div. 1 + Div. 2) Editorial | |
| 10188 | Binary Strings are Fun | combinatorics dp | Statement | C | Codeforces Round 838 (Div. 2) {1762} | PROGRAMMING | 1750.0 | Codeforces Round #838 (Div. 2) Editorial | |
| 2350 | Valid Bitonic Permutations | combinatorics dp implementation math | Statement | D | Codeforces Round 840 (Div. 2) and Enigma 2022 - Cybros LNMIIT {1763} | PROGRAMMING | 2000.0 | Codeforces Round #840 (Div. 2) and Enigma 2022 — Cybros LNMIIT Editorial | |
| 3158 | Doremy's Pegging Game | combinatorics geometry math | Statement | D | Codeforces Global Round 24 {1764} | PROGRAMMING | 1750.0 | Codeforces Global Round 24 Editorial | |
| 2277 | Partial Sorting | combinatorics fft math number theory | Statement | E | Codeforces Round 842 (Div. 2) {1768} | PROGRAMMING | 2250.0 | Codeforces Round #842 (Div. 2) Editorial | |
| 948 | Koxia and Sequence | bitmasks combinatorics math | Statement | F | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 2500.0 | Good Bye 2022 -- Editorial | |
| 1613 | Koxia and Tree | combinatorics dp math probabilities trees | Statement | E | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 2000.0 | Good Bye 2022 -- Editorial | |
| 25382 | Hossam and Combinatorics | combinatorics math sortings | Statement | A | Codeforces Round 837 (Div. 2) {1771} | PROGRAMMING | 500.0 | Codeforces Round #837 (Div. 2) Editorial | |
| 876 | Laboratory on Pluto | brute force combinatorics dp fft greedy math | Statement | F | Codeforces Round 843 (Div. 2) {1775} | PROGRAMMING | 3000.0 | Codeforces Round #843 (Div. 2) Editorial | |
| 3448 | Flexible String Revisit | combinatorics dp math probabilities | Statement | D | Codeforces Round 848 (Div. 2) {1778} | PROGRAMMING | 1750.0 | Codeforces Round #848 (Div. 2) Editorial | |
| 1324 | Bracket Insertion | brute force combinatorics constructive algorithms dp math trees | Statement | F | VK Cup 2022 - Отборочный раунд (Engine) {1781} | PROGRAMMING | 3250.0 | Tutorial | |
| 4700 | Moving Dots | binary search brute force combinatorics dp math two pointers | Statement | D | Codeforces Round 851 (Div. 2) {1788} | PROGRAMMING | 2250.0 | Codeforces Round #851 (Div. 2) Editorial | |
| 970 | Serval and Music Game | brute force combinatorics implementation math number theory | Statement | E | Codeforces Round 853 (Div. 2) {1789} | PROGRAMMING | 2000.0 | Codeforces Round #853 (Div. 2) Editorial | |
| 9971 | Serval and Toxel's Arrays | combinatorics implementation math | Statement | C | Codeforces Round 853 (Div. 2) {1789} | PROGRAMMING | 1250.0 | Codeforces Round #853 (Div. 2) Editorial | |
| 4526 | Counting Factorizations | combinatorics dp math number theory | Statement | D | Codeforces Round 856 (Div. 2) {1794} | PROGRAMMING | 2000.0 | Codeforces Round 856 (Div. 2) Editorial | |
| 13278 | Triangle Coloring | combinatorics math | Statement | D | Educational Codeforces Round 143 (Rated for Div. 2) {1795} | PROGRAMMING | 112963 | ||
| 12231 | Maximum Set | binary search brute force combinatorics dp math | Statement | C | Educational Codeforces Round 144 (Rated for Div. 2) {1796} | PROGRAMMING | Educational Codeforces Round 144 Editorial | ||
| 1080 | Count Voting | combinatorics dp math | Statement | G | Codeforces Round 854 by cybercats (Div. 1 + Div. 2) {1799} | PROGRAMMING | 3000.0 | Codeforces Round #854 Editorial | |
| 1196 | DSU Master | combinatorics dp dsu math | Statement | D | Codeforces Round 858 (Div. 2) {1806} | PROGRAMMING | 2000.0 | Codeforces Round #858 (Div. 2) Editorial | |
| 580 | Minibuses on Venus (hard version) | brute force combinatorics dp math | Statement | E3 | Codeforces Round 861 (Div. 2) {1808} | PROGRAMMING | 750.0 | Codeforces Round #861 (Div. 2) editorial | 2800 |
| 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 | ||
| 2520 | Vlad and the Nice Paths (easy version) | combinatorics dp math | Statement | G1 | Codeforces Round 863 (Div. 3) {1811} | PROGRAMMING | 114788 | ||
| 1506 | XOR Counting | bitmasks combinatorics dp math | Statement | D | Codeforces Round 865 (Div. 1) {1815} | PROGRAMMING | 2500.0 | Editorial of Codeforces Round #865 | 2600 |
| 957 | Timber | combinatorics dp fft math | Statement | F | Educational Codeforces Round 147 (Rated for Div. 2) {1821} | PROGRAMMING | 115296 | ||
| 21237 | Matching | combinatorics math | Statement | A | Educational Codeforces Round 147 (Rated for Div. 2) {1821} | PROGRAMMING | 115296 | ||
| 17205 | A-characteristic | combinatorics constructive algorithms math | Statement | A | Codeforces Round 868 (Div. 2) {1823} | PROGRAMMING | 500.0 | 115465 | |
| 6093 | LuoTianyi and the Floating Islands (Easy Version) | combinatorics math probabilities trees | Statement | B1 | Codeforces Round 872 (Div. 1) {1824} | PROGRAMMING | 500.0 | CodeForces Round 872(Div. 1&2) Editorial | 1800 |
| 3457 | LuoTianyi and the Floating Islands (Hard Version) | combinatorics dfs and similar math probabilities trees | Statement | B2 | Codeforces Round 872 (Div. 1) {1824} | PROGRAMMING | 750.0 | CodeForces Round 872(Div. 1&2) Editorial | 2300 |
| 29331 | Counting Orders | combinatorics math sortings two pointers | Statement | A | Codeforces Round 873 (Div. 1) {1827} | PROGRAMMING | 500.0 | Codeforces Round #873 (Div. 1 & 2) Editorial | 1100 |
| 10955 | Don't Blame Me | bitmasks combinatorics dp math | Statement | H | Codeforces Round 871 (Div. 4) {1829} | PROGRAMMING | Codeforces Round 871 (Div. 4) Editorial | 1700 | |
| 2213 | Hyperregular Bracket Strings | combinatorics hashing number theory sortings two pointers | Statement | C | Codeforces Round 875 (Div. 1) {1830} | PROGRAMMING | 1750.0 | Codeforces Round #875 (Div.1 + Div. 2) Editorial | |
| 1867 | Count Supersequences | combinatorics dp math | Statement | E | Codeforces Round 877 (Div. 2) {1838} | PROGRAMMING | 2250.0 | Codeforces Round #877 (Div. 2) Editorial | |
| 24790 | Binary Cafe | bitmasks combinatorics math | Statement | B | Codeforces Round 878 (Div. 3) {1840} | PROGRAMMING | Codeforces Round #878 (Div.3) Editorial | ||
| 48618 | Ski Resort | combinatorics math two pointers | Statement | C | Codeforces Round 878 (Div. 3) {1840} | PROGRAMMING | Codeforces Round #878 (Div.3) Editorial | ||
| 1609 | Tenzing and Random Operations | combinatorics dp math probabilities | Statement | G | CodeTON Round 5 (Div. 1 + Div. 2, Rated, Prizes!) {1842} | PROGRAMMING | 3000.0 | CodeTON Round 5 Editorial | |
| 295 | Multiple of Three Cycles | combinatorics dp dsu math | Statement | H | Codeforces Round 884 (Div. 1 + Div. 2) {1844} | PROGRAMMING | 4000.0 | Codeforces Round #884 (Div. 1 + Div. 2) Editorial | |
| 2051 | Vika and Wiki | binary search bitmasks combinatorics math | Statement | F | Codeforces Round 885 (Div. 2) {1848} | PROGRAMMING | 2750.0 | Codeforces Round #885 (Div.2) Editorial | |
| 15564 | 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 | ||
| 45936 | Longest Divisors Interval | brute force combinatorics greedy math number theory | Statement | B | Codeforces Round 889 (Div. 2) {1855} | PROGRAMMING | 1000.0 | Editorial of Codeforces Round 889 (Div. 1 + Div. 2) | |
| 19940 | Ice Cream Balls | binary search combinatorics constructive algorithms math | Statement | D | Codeforces Round 894 (Div. 3) {1862} | PROGRAMMING | Tutorial | ||
| 3072 | 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 | |
| 978 | Mighty Rock Tower | combinatorics dp math probabilities | Statement | M | COMPFEST 15 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1866} | PROGRAMMING | COMPFEST 15 Preliminary — Editorial | ||
| 9244 | Battling with Numbers | combinatorics math number theory | Statement | B | COMPFEST 15 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1866} | PROGRAMMING | COMPFEST 15 Preliminary — Editorial | ||
| 1378 | Travel Plan | combinatorics divide and conquer dp math trees | Statement | C | Codeforces Round 896 (Div. 1) {1868} | PROGRAMMING | 1000.0 | Codeforces Round 896 (Div. 1, Div. 2) Editorial | |
| 4155 | Counting Rhyme | brute force combinatorics dp math number theory sortings | Statement | D | Codeforces Round 904 (Div. 2) {1884} | PROGRAMMING | 2500.0 | Codeforces Round #904 (Div. 2) Editorial | |
| 4195 | Monocarp and the Set | brute force combinatorics math | Statement | D | Educational Codeforces Round 156 (Rated for Div. 2) {1886} | PROGRAMMING | Educational Codeforces Round 156 Editorial | ||
| 1054 | Fancy Arrays | combinatorics math matrices | Statement | F | Educational Codeforces Round 157 (Rated for Div. 2) {1895} | PROGRAMMING | Educational Codeforces Round 157 Editorial | ||
| 1273 | One-X | combinatorics dp math | Statement | E | Codeforces Round 915 (Div. 2) {1905} | PROGRAMMING | 2250.0 | Codeforces Round 915 (Div. 2) Editorial | |
| 179 | Short Permutation Problem | combinatorics dp fft math | Statement | I | Pinely Round 3 (Div. 1 + Div. 2) {1909} | PROGRAMMING | 6000.0 | Editorial of Pinely Round 3 (Div. 1 + Div. 2) | |
| 2265 | Small Permutation Problem (Easy Version) | combinatorics dp math | Statement | F1 | Pinely Round 3 (Div. 1 + Div. 2) {1909} | PROGRAMMING | 1500.0 | Editorial of Pinely Round 3 (Div. 1 + Div. 2) | |
| 1234 | Small Permutation Problem (Hard Version) | combinatorics dp math | Statement | F2 | Pinely Round 3 (Div. 1 + Div. 2) {1909} | PROGRAMMING | 1500.0 | Editorial of Pinely Round 3 (Div. 1 + Div. 2) | |
| 4274 | Kim's Quest | bitmasks combinatorics dp | Statement | K | 2023-2024 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1912} | PROGRAMMING | Tutorials (PDF) | 1800 | |
| 1445 | Blueprint for Seating | combinatorics divide and conquer fft math | Statement | B | 2023-2024 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1912} | PROGRAMMING | Tutorials (PDF) | 2000 | |
| 2413 | Light Bulbs (Easy Version) | brute force combinatorics dfs and similar dp dsu graphs math | Statement | G1 | Codeforces Round 916 (Div. 3) {1914} | PROGRAMMING | Codeforces Round 916 (Div. 3) Editorial | ||
| 719 | Matrix Rank (Easy Version) | brute force combinatorics dp math matrices | Statement | H1 | Good Bye 2023 {1916} | PROGRAMMING | 2750.0 | ||
| 634 | Matrix Rank (Hard Version) | combinatorics dp math matrices | Statement | H2 | Good Bye 2023 {1916} | PROGRAMMING | 1750.0 | ||
| 2083 | 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) | |
| 1136 | Counting Prefixes | combinatorics dp math | Statement | E | Hello 2024 {1919} | PROGRAMMING | 2250.0 | 2600 | |
| 3408 | Counting Binary Strings | combinatorics dp math strings | Statement | E | Codeforces Round 919 (Div. 2) {1920} | PROGRAMMING | 2250.0 | Editorial for Codeforces Round #919 (Div. 2) | |
| 23454 | Forming Triangles | combinatorics implementation math | Statement | B | Educational Codeforces Round 161 (Rated for Div. 2) {1922} | PROGRAMMING | Educational Codeforces Round 161 Editorial | ||
| 1439 | Balanced Subsequences | combinatorics dp math | Statement | D | Codeforces Round 921 (Div. 1) {1924} | PROGRAMMING | 1750.0 | Codeforces Round 921 (Div. 1, Div. 2) Editorial | |
| 1386 | Fractal Origami | combinatorics geometry math matrices | Statement | C | Codeforces Round 921 (Div. 1) {1924} | PROGRAMMING | 1500.0 | Codeforces Round 921 (Div. 1, Div. 2) Editorial | |
| 4817 | Good Trip | combinatorics dp math probabilities | Statement | D | Codeforces Round 921 (Div. 2) {1925} | PROGRAMMING | 1750.0 | Codeforces Round 921 (Div. 1, Div. 2) Editorial | |
| 347 | Digital Patterns | combinatorics data structures implementation math | Statement | F | Codeforces Round 924 (Div. 2) {1928} | PROGRAMMING | 2750.0 | Codeforces Round 924 Editorial | |
| 5801 | Sasha and a Walk in the City | combinatorics dfs and similar dp math trees | Statement | D | Codeforces Round 926 (Div. 2) {1929} | PROGRAMMING | 2000.0 | Codeforces Round #926 (Div. 2) Editorial. | |
| 2294 | Sasha and the Wedding Binary Search Tree | combinatorics dfs and similar math sortings trees | Statement | F | Codeforces Round 926 (Div. 2) {1929} | PROGRAMMING | 3000.0 | Codeforces Round #926 (Div. 2) Editorial. | |
| 1480 | 2..3...4.... Wonderful! Wonderful! | combinatorics math | Statement | E | think-cell Round 1 {1930} | PROGRAMMING | 2500.0 | think-cell Round 1 Editorial | |
| 3696 | One-Dimensional Puzzle | combinatorics constructive algorithms math number theory | Statement | G | Codeforces Round 925 (Div. 3) {1931} | PROGRAMMING | 125878 | ||
| 31275 | Divisible Pairs | combinatorics data structures hashing math | Statement | D | Codeforces Round 925 (Div. 3) {1931} | PROGRAMMING | 125878 | ||
| 1191 | Turtle Magic: Royal Turtle Shell Pattern | bitmasks brute force combinatorics math | Statement | G | Codeforces Round 929 (Div. 3) {1933} | PROGRAMMING | Codeforces Round 929 (Div. 3) Editorial | ||
| 10792 | Exam in MAC | binary search combinatorics math | Statement | D | Codeforces Round 932 (Div. 2) {1935} | PROGRAMMING | 1750.0 | Codeforces Round #932 (Div. 2) Editorial | |
| 1973 | Farm Game | combinatorics games math | Statement | E | CodeTON Round 8 (Div. 1 + Div. 2, Rated, Prizes!) {1942} | PROGRAMMING | 2500.0 | CodeTON Round 8 Editorial | |
| 762 | Bessie and Cards | combinatorics math | Statement | G | CodeTON Round 8 (Div. 1 + Div. 2, Rated, Prizes!) {1942} | PROGRAMMING | 3000.0 | CodeTON Round 8 Editorial | |
| 3186 | Girl Permutation | combinatorics dp math number theory | Statement | E | Codeforces Round 936 (Div. 2) {1946} | PROGRAMMING | 2250.0 | Codeforces Round #936 (Div. 2) Editorial | |
| 1654 | Rare Coins | combinatorics math probabilities | Statement | F | Educational Codeforces Round 163 (Rated for Div. 2) {1948} | PROGRAMMING | Educational Codeforces Round 163 Editorial | ||
| 426 | Clacking Balls | combinatorics math probabilities | Statement | G | Codeforces Global Round 25 {1951} | PROGRAMMING | 3250.0 | Codeforces Global Round 25 Editorial | |
| 345 | Sweep Line | combinatorics games math | Statement | E | April Fools Day Contest 2024 {1952} | PROGRAMMING | April Fools Day Contest 2024 Editorial | ||
| 8179 | Colored Balls | combinatorics dp greedy math sortings | Statement | D | Educational Codeforces Round 164 (Rated for Div. 2) {1954} | PROGRAMMING | Educational Codeforces Round 164 Editorial | ||
| 361 | Unique Strings | combinatorics dp math | Statement | F | Educational Codeforces Round 164 (Rated for Div. 2) {1954} | PROGRAMMING | Educational Codeforces Round 164 Editorial | ||
| 12011 | How Does the Rook Move? | combinatorics dp math | Statement | C | Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} | PROGRAMMING | 1500.0 | Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial | 1600 |
| 1629 | Carousel of Combinations | brute force combinatorics dp math number theory | Statement | E | Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} | PROGRAMMING | 2250.0 | Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial | 2400 |
| 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 |
| 396 | Again Counting Arrays (Easy Version) | combinatorics dp fft math | Statement | E1 | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1750.0 | Tutorial | 3100 |
| 219 | Again Counting Arrays (Hard Version) | combinatorics dp math | Statement | E2 | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1000.0 | Tutorial | 3500 |
| 1047 | Set | bitmasks brute force combinatorics dfs and similar divide and conquer dp math | Statement | F | Codeforces Round 947 (Div. 1 + Div. 2) {1975} | PROGRAMMING | 2500.0 | editorial_zh.pdf | 2600 |
| 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 | ||
| 1911 | Number of k-good subarrays | bitmasks combinatorics divide and conquer dp math meet-in-the-middle | Statement | E | Codeforces Round 955 (Div. 2, with prizes from NEAR!) {1982} | PROGRAMMING | 2500.0 | 130839 | |
| 2489 | I Love Balls | combinatorics math probabilities | Statement | E | Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} | PROGRAMMING | 2000.0 | ||
| 12302 | D-Function | bitmasks combinatorics math number theory | Statement | G | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 23622 | Secret Box | brute force combinatorics math | Statement | E | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 1919 | Permutation Problem (Simple Version) | brute force combinatorics math number theory | Statement | G1 | Codeforces Round 954 (Div. 3) {1986} | PROGRAMMING | 130762 | ||
| 430 | Heartbeat | combinatorics dp fft math | Statement | F | Codeforces Round 958 (Div. 2) {1988} | PROGRAMMING | 3500.0 | Editorial of Codeforces Round 958 (Div. 2) | |
| 4189 | Ultra-Meow | combinatorics math number theory | Statement | G | Codeforces Round 957 (Div. 3) {1992} | PROGRAMMING | Shayan's Video Tutorial | ||
| 12639 | Decode | brute force combinatorics implementation | Statement | E | Codeforces Round 962 (Div. 3) {1996} | PROGRAMMING | Codeforces Round 962 (Div. 3) Editorial | ||
| 14110 | Expected Median | combinatorics math | Statement | F | Codeforces Round 964 (Div. 4) {1999} | PROGRAMMING | Video Tutorial | ||
| 16313 | Photoshoot for Gorillas | combinatorics data structures greedy math | Statement | E | Codeforces Round 966 (Div. 3) {2000} | PROGRAMMING | 132689 | ||
| 1553 | Deterministic Heap (Easy Version) | brute force combinatorics dp | Statement | E1 | Codeforces Round 967 (Div. 2) {2001} | PROGRAMMING | 2000.0 | Video Tutorial | |
| 290 | Deterministic Heap (Hard Version) | combinatorics dp | Statement | E2 | Codeforces Round 967 (Div. 2) {2001} | PROGRAMMING | 2000.0 | Video Tutorial | |
| 336 | Speedbreaker Counting (Easy Version) | combinatorics dp games greedy implementation math | Statement | F1 | Codeforces Round 975 (Div. 1) {2018} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round 975 (Div. 1, Div. 2) | |
| 2373 | Card Game | combinatorics dp fft greedy math | Statement | E | Educational Codeforces Round 170 (Rated for Div. 2) {2025} | PROGRAMMING | Educational Codeforces Round 170 Editorial | ||
| 19706 | Binomial Coefficients, Kind Of | combinatorics math | Statement | B | Educational Codeforces Round 170 (Rated for Div. 2) {2025} | PROGRAMMING | Educational Codeforces Round 170 Editorial | ||
| 23783 | Minimise Oneness | brute force combinatorics constructive algorithms | Statement | B | Codeforces Round 979 (Div. 2) {2030} | PROGRAMMING | 500.0 | Codeforces Round 979 Editorial | |
| 1978 | 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 | |
| 263 | The Destruction of the Universe (Easy Version) | combinatorics math | Statement | G1 | Codeforces Round 979 (Div. 2) {2030} | PROGRAMMING | 3000.0 | Codeforces Round 979 Editorial | |
| 491 | Peanuts | combinatorics dp games math | Statement | F | Codeforces Round 983 (Div. 2) {2032} | PROGRAMMING | 3000.0 | Codeforces Round 983 (Div. 2) Editorial | |
| 2032 | Permutations Harmony | brute force combinatorics constructive algorithms greedy hashing implementation math | Statement | E | Rayan Programming Contest 2024 - Selection (Codeforces Round 989, Div. 1 + Div. 2) {2034} | PROGRAMMING | 2000.0 | Rayan 2024 Selection Round Editorial | |
| 898 | Khayyam's Royal Decree (Easy Version) | combinatorics dp math | Statement | F1 | Rayan Programming Contest 2024 - Selection (Codeforces Round 989, Div. 1 + Div. 2) {2034} | PROGRAMMING | 2000.0 | Rayan 2024 Selection Round Editorial | |
| 602 | Khayyam's Royal Decree (Hard Version) | combinatorics dp math | Statement | F2 | Rayan Programming Contest 2024 - Selection (Codeforces Round 989, Div. 1 + Div. 2) {2034} | PROGRAMMING | 2000.0 | Rayan 2024 Selection Round Editorial | |
| 3779 | Natlan Exploring | combinatorics dp math number theory | Statement | G | Codeforces Round 988 (Div. 3) {2037} | PROGRAMMING | Video Tutorial | ||
| 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 | ||
| 2385 | Shohag Loves Inversions | combinatorics constructive algorithms dp math | Statement | E | CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} | PROGRAMMING | 2750.0 | Editorial of CodeTON Round 9 (Div. 1 + Div. 2) | |
| 514 | Shohag Loves Counting (Easy Version) | combinatorics dp math number theory | Statement | F1 | CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} | PROGRAMMING | 2000.0 | Editorial of CodeTON Round 9 (Div. 1 + Div. 2) | |
| 2690 | Control of Randomness | combinatorics dfs and similar graphs greedy math probabilities trees | Statement | E | Codeforces Round 992 (Div. 2) {2040} | PROGRAMMING | 2250.0 | Codeforces Round #992 (Div.2) Editorial | |
| 462 | Number of Cubes | combinatorics math number theory | Statement | F | Codeforces Round 992 (Div. 2) {2040} | PROGRAMMING | 2750.0 | Codeforces Round #992 (Div.2) Editorial | |
| 747 | Kevin and Matrices | combinatorics math | Statement | G | Codeforces Global Round 28 {2048} | PROGRAMMING | 2250.0 | Tutorial | |
| 448 | Xor of Median (Easy Version) | bitmasks combinatorics dp math | Statement | F1 | Codeforces Round 997 (Div. 2) {2056} | PROGRAMMING | 2750.0 | Codeforces Round #997 (Div. 2) Editorial | |
| 1053 | Nested Segments | combinatorics dp math trees | Statement | E | Codeforces Round 997 (Div. 2) {2056} | PROGRAMMING | 2250.0 | Codeforces Round #997 (Div. 2) Editorial | |
| 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 | |
| 2541 | Bitwise Slides | bitmasks combinatorics dp math | Statement | C | Codeforces Round 1004 (Div. 1) {2066} | PROGRAMMING | 1250.0 | 139415 | |
| 1458 | Club of Young Aircraft Builders (easy version) | combinatorics dp math | Statement | D1 | Codeforces Round 1004 (Div. 1) {2066} | PROGRAMMING | 750.0 | 139415 | |
| 634 | Club of Young Aircraft Builders (hard version) | combinatorics dp math | Statement | D2 | Codeforces Round 1004 (Div. 1) {2066} | PROGRAMMING | 1250.0 | 139415 | |
| 8525 | Goodbye, Banker Life | bitmasks combinatorics constructive algorithms math number theory | Statement | F | Codeforces Round 1006 (Div. 3) {2072} | PROGRAMMING | Codeforces Round 1006 (Div. 3) Editorial | ||
| 615 | 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 | |
| 2393 | Binary Subsequence Value Sum | combinatorics dp fft implementation math | Statement | C | Codeforces Round 1008 (Div. 1) {2077} | PROGRAMMING | 1500.0 | Codeforces Round 1008 (Div. 1, Div. 2) Editorial | |
| 1803 | Blossom | combinatorics fft math | Statement | E | Teza Round 1 (Codeforces Round 1015, Div. 1 + Div. 2) {2084} | PROGRAMMING | 2250.0 | 141155 | |
| 8451 | Even String | combinatorics dp math strings | Statement | D | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 3870 | She knows... | combinatorics constructive algorithms graphs math | Statement | E | Codeforces Round 1014 (Div. 2) {2092} | PROGRAMMING | 2250.0 | Codeforces Round #1014 (Div. 2) Editorial | |
| 226 | Wonderful XOR Problem | bitmasks combinatorics dp fft math | Statement | H | Neowise Labs Contest 1 (Codeforces Round 1018, Div. 1 + Div. 2) {2096} | PROGRAMMING | 3500.0 | Neowise Labs Contest 1 (Codeforces Round 1018, Div. 1 + Div. 2) Editorial | |
| 1947 | Baggage Claim | combinatorics dsu graphs math trees | Statement | B | Codeforces Round 1021 (Div. 1) {2097} | PROGRAMMING | 1000.0 | 142316 | |
| 22211 | Permutation Warm-Up | combinatorics greedy math number theory | Statement | A | Codeforces Round 1022 (Div. 2) {2108} | PROGRAMMING | 500.0 | Codeforces Round 1022 Editorial | |
| 1803 | Binary String Wowee | combinatorics dp strings | Statement | E | Codeforces Round 1025 (Div. 2) {2109} | PROGRAMMING | 2500.0 | Codeforces Round 1025 (Div. 2) Editorial | |
| 3411 | Tree Colorings | combinatorics dp graphs math trees | Statement | E | Educational Codeforces Round 180 (Rated for Div. 2) {2112} | PROGRAMMING | Educational Codeforces Round 180 — Editorial | ||
| 971 | Gellyfish and Eternal Violet | combinatorics dp greedy math meet-in-the-middle probabilities | Statement | C | Codeforces Round 1028 (Div. 1) {2115} | PROGRAMMING | 1750.0 | Codeforces Round 1028 (Div.1, Div.2) Editorial | |
| 3500 | Token Removing | combinatorics dp math | Statement | D | Codeforces Round 1035 (Div. 2) {2119} | PROGRAMMING | 2250.0 | Codeforces Round 1035 (Div. 2) Editorial | |
| 5834 | Matrix game | combinatorics math | Statement | D | Codeforces Round 1033 (Div. 2) and CodeNite 2025 {2120} | PROGRAMMING | 1750.0 | Codeforces Round 1033 (Div. 2) and CodeNite 2025 Editorial | |
| 519 | Tree Parking | combinatorics math trees | Statement | G | Order Capital Round 1 (Codeforces Round 1038, Div. 1 + Div. 2) {2122} | PROGRAMMING | 4000.0 | Order Capital Round 1 (Codeforces Round 1038, Div. 1 + Div. 2) Editorial | |
| 1426 | Sets of Complementary Sums | combinatorics dp math two pointers | Statement | E | Educational Codeforces Round 181 (Rated for Div. 2) {2125} | PROGRAMMING | Educational Codeforces Round 181 Editorial | ||
| 22955 | Count Good Numbers | combinatorics math number theory | Statement | C | Educational Codeforces Round 181 (Rated for Div. 2) {2125} | PROGRAMMING | Educational Codeforces Round 181 Editorial | ||
| 1272 | Hamed and AghaBalaSar | combinatorics math | Statement | F | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 3000.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 12532 | Sum of LDS | combinatorics dp math | Statement | D | Codeforces Round 1039 (Div. 2) {2128} | PROGRAMMING | 1750.0 | Codeforces Round #1039 — Editorial | |
| 894 | Sea, You & copriMe | brute force combinatorics constructive algorithms graphs greedy math number theory | Statement | H | Codeforces Round 1042 (Div. 3) {2131} | PROGRAMMING | Codeforces Round 1042 (Div. 3) Editorial | ||
| 373 | Beyond the Palindrome (Easy Version) | combinatorics dp math | Statement | E1 | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 3000.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 169 | Beyond the Palindrome (Hard Version) | combinatorics dp math number theory | Statement | E2 | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 2000.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 649 | Antiamuny and Slider Movement | binary search brute force combinatorics implementation math | Statement | D | Codeforces Round 1048 (Div. 1) {2138} | PROGRAMMING | 2500.0 | Codeforces Round 1048 (Div. 1, Div. 2) Editorial | |
| 569 | Cost of Coloring | combinatorics fft math | Statement | G | Educational Codeforces Round 183 (Rated for Div. 2) {2145} | PROGRAMMING | Educational Codeforces Round 183 Editorial | ||
| 449 | Modular Tetration | combinatorics math number theory | Statement | G | Codeforces Global Round 29 (Div. 1 + Div. 2) {2147} | PROGRAMMING | 4500.0 | ||
| 858 | Attraction Theory | combinatorics dp implementation math | Statement | D | Codeforces Round 1053 (Div. 1) {2150} | PROGRAMMING | 2500.0 | Editorial of Codeforces Round 1053 (Div. 1, Div. 2) | |
| 6417 | Grid Counting | combinatorics math | Statement | B | Codeforces Round 1053 (Div. 1) {2150} | PROGRAMMING | 1000.0 | Editorial of Codeforces Round 1053 (Div. 1, Div. 2) | |
| 263 | Distinct GCDs (Hard Version) | combinatorics constructive algorithms graphs graphs graphs math number theory number theory | Statement | F2 | Codeforces Round 1067 (Div. 2) {2158} | PROGRAMMING | 1000.0 | Codeforces Round 1067 (Div. 2) Editorial | |
| 1905 | Twin Polynomials | combinatorics graph matchings graphs math | Statement | C | Codeforces Round 1058 (Div. 1) {2159} | PROGRAMMING | 1500.0 | Codeforces Round 1058 Editorial | |
| 793 | Left is Always Right | combinatorics math | Statement | E | Pinely Round 5 (Div. 1 + Div. 2) {2161} | PROGRAMMING | 3000.0 | ||
| 491 | 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 | |
| 747 | Chain Prefix Rank (Easy Version) | combinatorics dfs and similar dp math | Statement | F1 | Codeforces Global Round 30 (Div. 1 + Div. 2) {2164} | PROGRAMMING | 2500.0 | Codeforces Global Round 30 Editorial | |
| 343 | Subsequence Problem | combinatorics dp fft math | Statement | F | Educational Codeforces Round 184 (Rated for Div. 2) {2169} | PROGRAMMING | Educational Codeforces Round 184 Editorial | ||
| 2373 | Sakura Adachi and Optimal Sequences | bitmasks combinatorics greedy math | Statement | G | Codeforces Round 1065 (Div. 3) {2171} | PROGRAMMING | Codeforces Round 1065 (Div. 3) Editorial | ||
| 479 | Mosaic Tree | combinatorics dp fft math trees | Statement | F | Codeforces Round 1069 (Div. 1) {2174} | PROGRAMMING | 3500.0 | Codeforces Round 1069 Editorial | |
| 143 | Balance | combinatorics math | Statement | G | Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} | PROGRAMMING | 2750.0 | Codeforces Global Round 31 | |
| 9128 | Christmas Tree Decoration | combinatorics dp greedy math | Statement | D | Educational Codeforces Round 186 (Rated for Div. 2) {2182} | PROGRAMMING | Educational Codeforces Round 186 Editorial | ||
| 9713 | Unfair Game | combinatorics dp math | Statement | D | Codeforces Round 1072 (Div. 3) {2184} | PROGRAMMING | Codeforces Round 1072 (Div. 3) Editorial | ||
| 1978 | Little String (Hard Version) | binary search combinatorics dp greedy math number theory | Statement | D2 | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 750.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 4039 | Little String (Easy Version) | combinatorics dp math | Statement | D1 | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 2000.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 95 | Sum of MEX | *special combinatorics data structures dp math | Statement | H | Kotlin Heroes: Episode 14 {2199} | PROGRAMMING | 151783 | ||
| 157 | Self-Produced Sequences | *special combinatorics math | Statement | F | Kotlin Heroes: Episode 14 {2199} | PROGRAMMING | 151783 | ||
| 1087 | Operation Permutation | combinatorics dp math probabilities | Statement | G | Codeforces Round 1084 (Div. 3) {2200} | PROGRAMMING | Codeforces Round 1084 (Div. 3) Editorial | ||
| 2072 | Rigged Bracket Sequence | combinatorics dp | Statement | C | Codeforces Round 1082 (Div. 1) {2201} | PROGRAMMING | 1750.0 | Codeforces Round 1082 (Div. 1, Div. 2) Complete Editorial | |
| 1289 | Sum of Fractions | binary search combinatorics greedy math two pointers | Statement | F | Educational Codeforces Round 188 (Rated for Div. 2) {2204} | PROGRAMMING | Educational Codeforces Round 188 Editorial | ||
| 911 | N-MEX (Counting Version) | combinatorics math | Statement | E2 | Codeforces Round 1085 (Div. 1 + Div. 2) {2207} | PROGRAMMING | 1000.0 | Codeforces Round 1085 (Div. 1 + Div. 2) Editorial | |
| 3074 | AND-array | bitmasks combinatorics math | Statement | D | Nebius Round 2 (Codeforces Round 1088, Div. 1 + Div. 2) {2211} | PROGRAMMING | 2000.0 | Nebius Round 2 and Codeforces Round 1088 Editorial | |
| 811 | Interval Game | bitmasks combinatorics dp games greedy math probabilities | Statement | F | Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} | PROGRAMMING | 2750.0 | Tutorial | |
| 249 | 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 | |
| 514 | Amanojaku and Sequence (Easy Version) | combinatorics math | Statement | E1 | Codeforces Round 1098 (Div. 2) {2228} | PROGRAMMING | 2000.0 | Codeforces Round 1098 (Div. 2) Editorial |