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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 1761 | Partial Sums | combinatorics math number theory | Statement | C | Codeforces Round 138 (Div. 1) {223} | PROGRAMMING | Tutorial | 2200 | |
| 600 | Gifts | combinatorics dp math probabilities | Statement | E | Codeforces Round 142 (Div. 1) {229} | PROGRAMMING | Codeforces Round #142 Problem Analysis | 2500 | |
| 953 | Number Challenge | combinatorics dp implementation math number theory | Statement | E | Codeforces Round 146 (Div. 1) {235} | PROGRAMMING | Codeforces Round #146 Tutorial | 2600 | |
| 1242 | Vasily the Bear and Beautiful Strings | combinatorics math number theory | Statement | D | Codeforces Round 195 (Div. 2) {336} | PROGRAMMING | Tutorial Codeforces Round #195 (Div. 2) | 2400 | |
| 1647 | On Number of Decompositions into Multipliers | combinatorics math number theory | Statement | A | Codeforces Round 232 (Div. 1) {396} | PROGRAMMING | 500.0 | Codeforces Round #232 Editorial (restored) | |
| 2119 | Pluses everywhere | combinatorics dp math number theory | Statement | E | Codeforces Round 295 (Div. 2) {520} | PROGRAMMING | Codeforces Round #295 Editorial (now with bonuses!) | 2500 | |
| 3504 | Mike and Foam | bitmasks combinatorics dp math number theory | Statement | C | Codeforces Round 305 (Div. 1) {547} | PROGRAMMING | Codeforces Round #305 Editorial | 2700 | |
| 2132 | GukiZ and Binary Operations | combinatorics implementation math matrices number theory | Statement | D | Codeforces Round 307 (Div. 2) {551} | PROGRAMMING | Tutorial | 2400 | |
| 8290 | Gerald and Giant Chess | combinatorics dp math number theory | Statement | C | Codeforces Round 313 (Div. 1) {559} | PROGRAMMING | Codeforces Round 313 — Extended editoral | 2500 | |
| 1262 | Present for Vitalik the Philatelist | combinatorics math number theory | Statement | E | Codeforces Round 325 (Div. 1) {585} | PROGRAMMING | Разбор Codeforces Round #325 | 2800 | |
| 2718 | Moodular Arithmetic | combinatorics dfs and similar dsu math number theory | Statement | B | Codeforces Round 334 (Div. 1) {603} | PROGRAMMING | Codeforces Round #334 Editorial | 2000 | |
| 6366 | Wet Shark and Flowers | combinatorics math number theory probabilities | Statement | C | Codeforces Round 341 (Div. 2) {621} | PROGRAMMING | 1700 | ||
| 1008 | Cowslip Collections | combinatorics math number theory | Statement | F | CROC 2016 - Elimination Round {645} | PROGRAMMING | Editorial for CROC 2016 Elimination Round | 2500 | |
| 709 | Move by Prime | combinatorics math number theory | Statement | G | IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} | PROGRAMMING | IndiaHacks Finals 2016 — Editorial | 3000 | |
| 1105 | PolandBall and Many Other Balls | combinatorics divide and conquer dp fft math number theory | Statement | G | 8VC Venture Cup 2017 - Elimination Round {755} | PROGRAMMING | 8VC Venture Cup 2017 — Elimination Round [Editorial] | 3100 | |
| 1147 | Barrels and boxes | brute force combinatorics math number theory probabilities | Statement | F | Divide by Zero 2017 and Codeforces Round 399 (Div. 1 + Div. 2, combined) {768} | PROGRAMMING | Editorial Divide by Zero and Codeforces Round #399 (Div. 1+2, combined) | 2300 | |
| 267 | Test Data Generation | combinatorics divide and conquer dp fft math number theory | Statement | F | VK Cup 2017 - Round 3 {773} | PROGRAMMING | VK Cup 2017 Round 3 + Codeforces Round #412 -- Tutorial | 3400 | |
| 3791 | Anton and School - 2 | combinatorics dp math number theory | Statement | D | Codeforces Round 404 (Div. 2) {785} | PROGRAMMING | Editorial | 2200 | |
| 3648 | Winter is here | combinatorics dp math number theory | Statement | D | Codeforces Round 428 (Div. 2) {839} | PROGRAMMING | Codeforces Round #428 editorial | 2200 | |
| 7553 | Leha and Function | combinatorics greedy math number theory sortings | Statement | A | Codeforces Round 429 (Div. 1) {840} | PROGRAMMING | Editorial | 1300 | |
| 667 | Product transformation | combinatorics math number theory | Statement | F | Bubble Cup X - Finals [Online Mirror] {852} | PROGRAMMING | Tutorial | 2300 | |
| 4293 | Counting Arrays | combinatorics dp math number theory | Statement | E | Educational Codeforces Round 33 (Rated for Div. 2) {893} | PROGRAMMING | 55989 | 2000 | |
| 4718 | Ralph And His Magic Field | combinatorics constructive algorithms math number theory | Statement | B | Codeforces Round 447 (Div. 2) {894} | PROGRAMMING | Codeforces Round #447 (Div.2 Only) Editorial | 1800 | |
| 681 | Nephren Runs a Cinema | chinese remainder theorem combinatorics math number theory | Statement | D | Codeforces Round 449 (Div. 1) {896} | PROGRAMMING | Codeforces Round #449 Editorial | 2800 | |
| 3869 | Unusual Sequences | bitmasks combinatorics dp math number theory | Statement | D | Codeforces Round 450 (Div. 2) {900} | PROGRAMMING | Codeforces Round #450(Div. 2). Editorial. | 2100 | |
| 2044 | List Of Integers | binary search bitmasks brute force combinatorics math number theory | Statement | G | Educational Codeforces Round 37 (Rated for Div. 2) {920} | PROGRAMMING | T | 2300 | |
| 1752 | Partitions | combinatorics math number theory | Statement | G | Educational Codeforces Round 41 (Rated for Div. 2) {961} | PROGRAMMING | Educational Codeforces Round 41 Editorial | 2700 | |
| 1053 | 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 | |
| 1891 | Relatively Prime Powers | combinatorics math number theory | Statement | F | Educational Codeforces Round 50 (Rated for Div. 2) {1036} | PROGRAMMING | 61727 | 2400 | |
| 3106 | 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 | |
| 1535 | 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 | |
| 1821 | 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 | |
| 8226 | Submarine in the Rybinsk Sea (easy edition) | combinatorics math number theory | Statement | D1 | Codeforces Round 574 (Div. 2) {1195} | PROGRAMMING | Разбор Codeforces Round #574 (Div. 2) | 1500 | |
| 4915 | Submarine in the Rybinsk Sea (hard edition) | combinatorics math number theory | Statement | D2 | Codeforces Round 574 (Div. 2) {1195} | PROGRAMMING | Разбор Codeforces Round #574 (Div. 2) | 1700 | |
| 2156 | Natasha, Sasha and the Prefix Sums | combinatorics dp math number theory | Statement | E | Codeforces Round 581 (Div. 2) {1204} | PROGRAMMING | 69244 | 2400 | |
| 2681 | Cards | combinatorics dp math number theory probabilities | Statement | F | Educational Codeforces Round 78 (Rated for Div. 2) {1278} | PROGRAMMING | Educational Codeforces Round 78 Editorial | 2600 | |
| 19576 | Kuroni and Impossible Calculation | brute force combinatorics math number theory | Statement | C | Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} | PROGRAMMING | 1250.0 | Ozon Tech Challenge 2020 Editorial | 1600 |
| 3219 | Divisor Paths | combinatorics graphs greedy math number theory | Statement | E | Educational Codeforces Round 85 (Rated for Div. 2) {1334} | PROGRAMMING | Educational Codeforces Round 85 Editorial | ||
| 6829 | Modular Stability | combinatorics math number theory | Statement | E | Educational Codeforces Round 88 (Rated for Div. 2) {1359} | PROGRAMMING | Educational Codeforces Round 88 Editorial | 2000 | |
| 5543 | Asterism (Easy Version) | brute force combinatorics implementation math number theory sortings | Statement | E1 | Codeforces Round 654 (Div. 2) {1371} | PROGRAMMING | 1500.0 | Codeforces Round #654 (Div. 2) Editorial | |
| 668 | Sum Over Subsets | combinatorics math number theory | Statement | F | Codeforces Round 678 (Div. 2) {1436} | PROGRAMMING | 3000.0 | Codeforces Round #678 (Div. 2). Editorial | |
| 2785 | Mocha and Stars | combinatorics dp fft math number theory | Statement | E | Codeforces Round 738 (Div. 2) {1559} | PROGRAMMING | 3000.0 | Tutorial (en) | 2200 |
| 3085 | Not Quite Lee | combinatorics math number theory | Statement | D | Codeforces Global Round 17 {1610} | PROGRAMMING | 2250.0 | Codeforces Global Round 17 Editorial | |
| 922 | A Random Code Problem | combinatorics dp math number theory | Statement | F | Educational Codeforces Round 121 (Rated for Div. 2) {1626} | PROGRAMMING | 99136 | ||
| 482 | Basis | combinatorics fft math number theory | Statement | F | Educational Codeforces Round 123 (Rated for Div. 2) {1644} | PROGRAMMING | 100227 | ||
| 3643 | 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 | |
| 816 | Power or XOR? | combinatorics math number theory | Statement | E | Codeforces Round 785 (Div. 2) {1673} | PROGRAMMING | 2750.0 | Codeforces Round #785 (Div. 2) Editorial | |
| 320 | 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 | |
| 2523 | 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 | |
| 1658 | 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 | |
| 1451 | Bags with Balls | combinatorics math number theory | Statement | F | Educational Codeforces Round 133 (Rated for Div. 2) {1716} | PROGRAMMING | 105653 | ||
| 7550 | 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 | |
| 2341 | Partial Sorting | combinatorics fft math number theory | Statement | E | Codeforces Round 842 (Div. 2) {1768} | PROGRAMMING | 2250.0 | Codeforces Round #842 (Div. 2) Editorial | |
| 994 | 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 | |
| 4595 | Counting Factorizations | combinatorics dp math number theory | Statement | D | Codeforces Round 856 (Div. 2) {1794} | PROGRAMMING | 2000.0 | Codeforces Round 856 (Div. 2) Editorial | |
| 47748 | 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) | |
| 9365 | 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 | ||
| 4243 | 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 | |
| 3782 | One-Dimensional Puzzle | combinatorics constructive algorithms math number theory | Statement | G | Codeforces Round 925 (Div. 3) {1931} | PROGRAMMING | 125878 | ||
| 3227 | Girl Permutation | combinatorics dp math number theory | Statement | E | Codeforces Round 936 (Div. 2) {1946} | PROGRAMMING | 2250.0 | Codeforces Round #936 (Div. 2) Editorial | |
| 1662 | 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 |
| 12473 | D-Function | bitmasks combinatorics math number theory | Statement | G | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 1949 | Permutation Problem (Simple Version) | brute force combinatorics math number theory | Statement | G1 | Codeforces Round 954 (Div. 3) {1986} | PROGRAMMING | 130762 | ||
| 4290 | Ultra-Meow | combinatorics math number theory | Statement | G | Codeforces Round 957 (Div. 3) {1992} | PROGRAMMING | Shayan's Video Tutorial | ||
| 3841 | Natlan Exploring | combinatorics dp math number theory | Statement | G | Codeforces Round 988 (Div. 3) {2037} | PROGRAMMING | Video Tutorial | ||
| 518 | 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) | |
| 468 | Number of Cubes | combinatorics math number theory | Statement | F | Codeforces Round 992 (Div. 2) {2040} | PROGRAMMING | 2750.0 | Codeforces Round #992 (Div.2) Editorial | |
| 8652 | 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 | ||
| 22329 | Permutation Warm-Up | combinatorics greedy math number theory | Statement | A | Codeforces Round 1022 (Div. 2) {2108} | PROGRAMMING | 500.0 | Codeforces Round 1022 Editorial | |
| 23294 | Count Good Numbers | combinatorics math number theory | Statement | C | Educational Codeforces Round 181 (Rated for Div. 2) {2125} | PROGRAMMING | Educational Codeforces Round 181 Editorial | ||
| 906 | 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 | ||
| 180 | 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 | |
| 646 | Modular Tetration | combinatorics math number theory | Statement | G | Codeforces Global Round 29 (Div. 1 + Div. 2) {2147} | PROGRAMMING | 4500.0 | ||
| 287 | 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 | |
| 2052 | 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 | |
| 914 | Elections in Saransk (hard version) | combinatorics dp fft math number theory | Statement | F2 | Codeforces Round 1103 (Div. 3) {2236} | PROGRAMMING | |||
| 5344 | Fair and Square | combinatorics dp graphs math number theory trees | Statement | E | Codeforces Round 1107 (Div. 3) {2241} | PROGRAMMING |