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9925 Make a Palindrome greedy sortings Statement D EPIC Institute of Technology Round Summer 2025 (Codeforces Round 1036, Div. 1 + Div. 2) {2124} PROGRAMMING 1750.0 EPIC Institute of Technology Round Summer 2025 (Codeforces Round 1036, Div. 1 + Div. 2) Editorial
1456 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
23540 Count Good Numbers combinatorics math number theory Statement C Educational Codeforces Round 181 (Rated for Div. 2) {2125} PROGRAMMING Educational Codeforces Round 181 Editorial
28688 Left and Down greedy math number theory Statement B Educational Codeforces Round 181 (Rated for Div. 2) {2125} PROGRAMMING Educational Codeforces Round 181 Editorial
53881 Only One Digit implementation math Statement A Codeforces Round 1037 (Div. 3) {2126} PROGRAMMING 144845
17725 G-C-D, Unlucky! math number theory Statement E Codeforces Round 1037 (Div. 3) {2126} PROGRAMMING 144845
147 Inter Active (Hard Version) binary search bitmasks constructive algorithms graphs implementation interactive math probabilities Statement G2 Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} PROGRAMMING 2750.0 Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial
2865 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
22032 Mix Mex Max constructive algorithms greedy math Statement A Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} PROGRAMMING 500.0 Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial
13046 Sum of LDS combinatorics dp math Statement D Codeforces Round 1039 (Div. 2) {2128} PROGRAMMING 1750.0 Codeforces Round #1039 — Editorial
408 Strict Triangle graphs shortest paths Statement F Codeforces Round 1039 (Div. 2) {2128} PROGRAMMING 4000.0 Codeforces Round #1039 — Editorial
2249 Interactive RBS (Hard Version) binary search bitmasks constructive algorithms dp interactive Statement C3 Codeforces Round 1040 (Div. 1) {2129} PROGRAMMING 750.0 Codeforces Round 1040 (Div. 1, Div. 2) Editorial
5199 Interactive RBS (Easy Version) binary search bitmasks constructive algorithms interactive Statement C1 Codeforces Round 1040 (Div. 1) {2129} PROGRAMMING 750.0 Codeforces Round 1040 (Div. 1, Div. 2) Editorial
3802 Interactive RBS (Medium Version) binary search bitmasks constructive algorithms interactive Statement C2 Codeforces Round 1040 (Div. 1) {2129} PROGRAMMING 750.0 Codeforces Round 1040 (Div. 1, Div. 2) Editorial
29201 Submission is All You Need greedy math Statement A Codeforces Round 1040 (Div. 2) {2130} PROGRAMMING 500.0 Codeforces Round 1040 (Div. 1, Div. 2) Editorial
4856 Unjust Binary Life binary search binary search data structures greedy greedy math two pointers Statement F Codeforces Round 1042 (Div. 3) {2131} PROGRAMMING Codeforces Round 1042 (Div. 3) Editorial
3915 Wafu! bitmasks brute force dp math Statement G Codeforces Round 1042 (Div. 3) {2131} PROGRAMMING Codeforces Round 1042 (Div. 3) Editorial
929 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
31675 Alternating Series constructive algorithms greedy math Statement B Codeforces Round 1042 (Div. 3) {2131} PROGRAMMING Codeforces Round 1042 (Div. 3) Editorial
39911 Lever math Statement A Codeforces Round 1042 (Div. 3) {2131} PROGRAMMING Codeforces Round 1042 (Div. 3) Editorial
22493 Make it Equal math number theory Statement C Codeforces Round 1042 (Div. 3) {2131} PROGRAMMING Codeforces Round 1042 (Div. 3) Editorial
9257 From 1 to Infinity binary search dp implementation math Statement D Codeforces Round 1043 (Div. 3) {2132} PROGRAMMING Codeforces Round 1043 (Div. 3) Editorial
13924 The Cunning Seller (hard version) binary search greedy math Statement C2 Codeforces Round 1043 (Div. 3) {2132} PROGRAMMING Codeforces Round 1043 (Div. 3) Editorial
28787 The Cunning Seller (easy version) greedy math Statement C1 Codeforces Round 1043 (Div. 3) {2132} PROGRAMMING Codeforces Round 1043 (Div. 3) Editorial
34732 The Secret Number math Statement B Codeforces Round 1043 (Div. 3) {2132} PROGRAMMING Codeforces Round 1043 (Div. 3) Editorial
7888 Chicken Jockey binary search brute force dp greedy math Statement D Codeforces Round 1044 (Div. 2) {2133} PROGRAMMING 2250.0 Codeforces Round 1044 (Div. 2) Editorial
32051 Redstone? brute force implementation math Statement A Codeforces Round 1044 (Div. 2) {2133} PROGRAMMING 500.0 Codeforces Round 1044 (Div. 2) Editorial
525 Flint and Steel data structures dp Statement F Codeforces Round 1044 (Div. 2) {2133} PROGRAMMING 3250.0 Codeforces Round 1044 (Div. 2) Editorial
27563 Painting With Two Colors constructive algorithms implementation math Statement A Codeforces Round 1045 (Div. 2) {2134} PROGRAMMING 500.0 145832
22135 Add 0 or K constructive algorithms math number theory Statement B Codeforces Round 1045 (Div. 2) {2134} PROGRAMMING 1250.0 145832
1445 From the Unknown (Hard Version) binary search brute force constructive algorithms interactive math Statement D2 Codeforces Round 1046 (Div. 1) {2135} PROGRAMMING 1250.0 Codeforces Round 1046 (Div. 1, Div. 2) Editorial
1307 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
266 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
9347 For the Champion constructive algorithms interactive math Statement B Codeforces Round 1046 (Div. 1) {2135} PROGRAMMING 1000.0 Codeforces Round 1046 (Div. 1, Div. 2) Editorial
4209 From the Unknown (Easy Version) constructive algorithms interactive math Statement D1 Codeforces Round 1046 (Div. 1) {2135} PROGRAMMING 1250.0 Codeforces Round 1046 (Div. 1, Div. 2) Editorial
617 To the Infinity data structures hashing math trees Statement F Codeforces Round 1046 (Div. 1) {2135} PROGRAMMING 4000.0 Codeforces Round 1046 (Div. 1, Div. 2) Editorial
21865 Like the Bitset constructive algorithms greedy two pointers Statement B Codeforces Round 1046 (Div. 2) {2136} PROGRAMMING 1000.0 Codeforces Round 1046 (Div. 1, Div. 2) Editorial
27122 In the Dream greedy math Statement A Codeforces Round 1046 (Div. 2) {2136} PROGRAMMING 500.0 Codeforces Round 1046 (Div. 1, Div. 2) Editorial
23983 Maximum Even Sum brute force greedy implementation math Statement C Codeforces Round 1047 (Div. 3) {2137} PROGRAMMING Codeforces Round 1047 (Div. 3) Editorial
36584 Collatz Conjecture constructive algorithms math Statement A Codeforces Round 1047 (Div. 3) {2137} PROGRAMMING Codeforces Round 1047 (Div. 3) Editorial
27647 Fun Permutation constructive algorithms math number theory Statement B Codeforces Round 1047 (Div. 3) {2137} PROGRAMMING Codeforces Round 1047 (Div. 3) Editorial
10808 Mexification implementation math Statement E Codeforces Round 1047 (Div. 3) {2137} PROGRAMMING Codeforces Round 1047 (Div. 3) Editorial
685 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
17872 Cake Assignment bitmasks constructive algorithms Statement A Codeforces Round 1048 (Div. 1) {2138} PROGRAMMING 500.0 Codeforces Round 1048 (Div. 1, Div. 2) Editorial
26859 Maple and Multiplication greedy math Statement A Codeforces Round 1048 (Div. 2) {2139} PROGRAMMING 500.0 Codeforces Round 1048 (Div. 1, Div. 2) Editorial
23496 Another Divisibility Problem constructive algorithms math number theory Statement B Codeforces Round 1049 (Div. 2) {2140} PROGRAMMING 1000.0 Codeforces Round 1049 (Div. 2) Editorial
5241 A Cruel Segment's Thesis greedy math sortings Statement D Codeforces Round 1049 (Div. 2) {2140} PROGRAMMING 1750.0 Codeforces Round 1049 (Div. 2) Editorial
492 Avoid Minimums *special greedy math Statement D Kotlin Heroes: Episode 13 {2141} PROGRAMMING Kotlin Heroes 13 Editorial
2130 Make Good constructive algorithms math strings Statement E Codeforces Round 1051 (Div. 2) {2143} PROGRAMMING 2500.0 Codeforces Round 1051 (Div. 2) Editorial
462 Increasing Xor data structures math Statement F Codeforces Round 1051 (Div. 2) {2143} PROGRAMMING 3000.0 Codeforces Round 1051 (Div. 2) Editorial
22497 Cut the Array brute force math number theory Statement A Educational Codeforces Round 182 (Rated for Div. 2) {2144} PROGRAMMING Educational Codeforces Round 182 Editorial
7477 Price Tags dp math Statement D Educational Codeforces Round 182 (Rated for Div. 2) {2144} PROGRAMMING Educational Codeforces Round 182 Editorial
3281 Predicting Popularity binary search data structures math sortings Statement E Educational Codeforces Round 183 (Rated for Div. 2) {2145} PROGRAMMING Educational Codeforces Round 183 Editorial
32400 Candies for Nephews brute force math Statement A Educational Codeforces Round 183 (Rated for Div. 2) {2145} PROGRAMMING Educational Codeforces Round 183 Editorial
650 Cost of Coloring combinatorics fft math Statement G Educational Codeforces Round 183 (Rated for Div. 2) {2145} PROGRAMMING Educational Codeforces Round 183 Editorial
7134 Inversion Value of a Permutation constructive algorithms dfs and similar dp math Statement D Educational Codeforces Round 183 (Rated for Div. 2) {2145} PROGRAMMING Educational Codeforces Round 183 Editorial
14131 Wrong Binary Search binary search constructive algorithms Statement C Codeforces Round 1052 (Div. 2) {2146} PROGRAMMING 1250.0 Codeforces Round 1052 (Div. 2) Editorial
1227 Modular Tetration combinatorics math number theory Statement G Codeforces Global Round 29 (Div. 1 + Div. 2) {2147} PROGRAMMING 4500.0
50310 Sublime Sequence brute force math Statement A Codeforces Round 1050 (Div. 4) {2148} PROGRAMMING Codeforces Round 1050 (Div. 4) Editorial
4411 Farmer John's Last Wish data structures math number theory Statement G Codeforces Round 1050 (Div. 4) {2148} PROGRAMMING Codeforces Round 1050 (Div. 4) Editorial
26581 Pacer greedy math Statement C Codeforces Round 1050 (Div. 4) {2148} PROGRAMMING Codeforces Round 1050 (Div. 4) Editorial
5075 Nezuko in the Clearing binary search math ternary search Statement F Codeforces Round 1054 (Div. 3) {2149} PROGRAMMING __rose
43159 Be Positive math Statement A Codeforces Round 1054 (Div. 3) {2149} PROGRAMMING __rose
399 Counting Is Fun: The Finale Statement G Codeforces Round 1053 (Div. 1) {2150} PROGRAMMING 4250.0 Editorial of Codeforces Round 1053 (Div. 1, Div. 2)
1298 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)
8338 Grid Counting combinatorics math Statement B Codeforces Round 1053 (Div. 1) {2150} PROGRAMMING 1000.0 Editorial of Codeforces Round 1053 (Div. 1, Div. 2)
805 Hidden Single (Version 2) divide and conquer interactive math probabilities Statement E2 Codeforces Round 1053 (Div. 1) {2150} PROGRAMMING 1750.0 Editorial of Codeforces Round 1053 (Div. 1, Div. 2)
2807 Hidden Single (Version 1) divide and conquer interactive math probabilities sortings Statement E1 Codeforces Round 1053 (Div. 1) {2150} PROGRAMMING 2000.0 Editorial of Codeforces Round 1053 (Div. 1, Div. 2)
4694 Monotone Subsequence brute force constructive algorithms dp graphs interactive math Statement E Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) {2152} PROGRAMMING 3000.0 Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) Editorial
3841 Query Jungle data structures data structures implementation math math trees Statement G Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) {2152} PROGRAMMING 4000.0 Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) Editorial
14837 Triple Removal data structures greedy math Statement C Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) {2152} PROGRAMMING 1500.0 Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) Editorial
14877 Catching the Krug games math Statement B Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) {2152} PROGRAMMING 1500.0 Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) Editorial
23341 Bitwise Reversion bitmasks Statement B Codeforces Round 1057 (Div. 2) {2153} PROGRAMMING 750.0 Codeforces Round 1057 (Div. 2) Editorial
1047 Zero Trailing Factorial brute force math number theory Statement E Codeforces Round 1057 (Div. 2) {2153} PROGRAMMING 2250.0 Codeforces Round 1057 (Div. 2) Editorial
343 Odd Queries on Odd Array data structures trees Statement F Codeforces Round 1057 (Div. 2) {2153} PROGRAMMING 3250.0 Codeforces Round 1057 (Div. 2) Editorial
1260 No Mind To Think binary search greedy sortings ternary search two pointers Statement E Codeforces Round 1060 (Div. 2) {2154} PROGRAMMING 2500.0 Codeforces Round 1060 (Div. 2) Editorial
14333 No Cost Too Great (Easy Version) greedy implementation math number theory Statement C1 Codeforces Round 1060 (Div. 2) {2154} PROGRAMMING 1250.0 Codeforces Round 1060 (Div. 2) Editorial
5778 No Cost Too Great (Hard Version) greedy math number theory Statement C2 Codeforces Round 1060 (Div. 2) {2154} PROGRAMMING 1000.0 Codeforces Round 1060 (Div. 2) Editorial
23916 Notelock greedy two pointers Statement A Codeforces Round 1060 (Div. 2) {2154} PROGRAMMING 500.0 Codeforces Round 1060 (Div. 2) Editorial
3138 Mimo & Yuyu games greedy math Statement E Codeforces Round 1056 (Div. 2) {2155} PROGRAMMING 2250.0 Codeforces Round 1056 (Div. 2) Editorial
26169 El fucho implementation math Statement A Codeforces Round 1056 (Div. 2) {2155} PROGRAMMING 500.0 Codeforces Round 1056 (Div. 2) Editorial
6293 Batteries interactive math Statement D Codeforces Round 1056 (Div. 2) {2155} PROGRAMMING 2000.0 Codeforces Round 1056 (Div. 2) Editorial
21782 Strange Machine binary search brute force greedy implementation Statement B Codeforces Round 1061 (Div. 2) {2156} PROGRAMMING 750.0 Codeforces Round 1061 (Div. 2) Editorial
5595 Find the Last Number bitmasks constructive algorithms interactive math Statement D Codeforces Round 1061 (Div. 2) {2156} PROGRAMMING 2000.0 Codeforces Round 1061 (Div. 2) Editorial
13016 Maximum GCD on Whiteboard greedy math number theory Statement C Codeforces Round 1061 (Div. 2) {2156} PROGRAMMING 1500.0 Codeforces Round 1061 (Div. 2) Editorial
924 Isaac's Queries brute force constructive algorithms dfs and similar divide and conquer greedy interactive math probabilities Statement G Codeforces Round 1066 (Div. 1 + Div. 2) {2157} PROGRAMMING 3000.0 Codeforces Round 1066 (Div. 1 + Div. 2) Editorial
11753 Meximum Array 2 constructive algorithms greedy math Statement C Codeforces Round 1066 (Div. 1 + Div. 2) {2157} PROGRAMMING 1500.0 Codeforces Round 1066 (Div. 1 + Div. 2) Editorial
8232 Billion Players Game greedy math sortings ternary search two pointers Statement D Codeforces Round 1066 (Div. 1 + Div. 2) {2157} PROGRAMMING 1500.0 Codeforces Round 1066 (Div. 1 + Div. 2) Editorial
15368 Expansion Plan 2 implementation math Statement B Codeforces Round 1066 (Div. 1 + Div. 2) {2157} PROGRAMMING 1000.0 Codeforces Round 1066 (Div. 1 + Div. 2) Editorial
3480 Palindrome Flipping brute force constructive algorithms implementation strings Statement D Codeforces Round 1067 (Div. 2) {2158} PROGRAMMING 2000.0 Codeforces Round 1067 (Div. 2) Editorial
295 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
14923 Split constructive algorithms greedy math Statement B Codeforces Round 1067 (Div. 2) {2158} PROGRAMMING 1250.0 Codeforces Round 1067 (Div. 2) Editorial
24312 Suspension greedy math Statement A Codeforces Round 1067 (Div. 2) {2158} PROGRAMMING 500.0 Codeforces Round 1067 (Div. 2) Editorial
2282 Inverse Minimum Partition (Easy Version) binary search data structures dp greedy math two pointers Statement D1 Codeforces Round 1058 (Div. 1) {2159} PROGRAMMING 1500.0 Codeforces Round 1058 Editorial
3419 Twin Polynomials combinatorics graph matchings graphs math Statement C Codeforces Round 1058 (Div. 1) {2159} PROGRAMMING 1500.0 Codeforces Round 1058 Editorial
477 Inverse Minimum Partition (Hard Version) dp greedy Statement D2 Codeforces Round 1058 (Div. 1) {2159} PROGRAMMING 1750.0 Codeforces Round 1058 Editorial
2259 Super-Short-Polynomial-San math math meet-in-the-middle meet-in-the-middle Statement E Codeforces Round 1058 (Div. 1) {2159} PROGRAMMING 3000.0 Codeforces Round 1058 Editorial
18558 Distinct Elements greedy math Statement B Codeforces Round 1058 (Div. 2) {2160} PROGRAMMING 1000.0 Codeforces Round 1058 Editorial
23083 MEX Partition math Statement A Codeforces Round 1058 (Div. 2) {2160} PROGRAMMING 500.0 Codeforces Round 1058 Editorial
816 Left is Always Right combinatorics math Statement E Pinely Round 5 (Div. 1 + Div. 2) {2161} PROGRAMMING 3000.0
16128 Round Trip games greedy implementation math Statement A Pinely Round 5 (Div. 1 + Div. 2) {2161} PROGRAMMING 500.0
2946 Beautiful Tree constructive algorithms math trees Statement G Codeforces Round 1059 (Div. 3) {2162} PROGRAMMING Codeforces Round 1059 (Div. 3) Editorial
9606 Siga ta Kymata constructive algorithms math Statement B Codeforces Round 1063 (Div. 2) {2163} PROGRAMMING 1000.0 Codeforces Round 1063 Editorial
9718 Monopati dp math two pointers Statement C Codeforces Round 1063 (Div. 2) {2163} PROGRAMMING 1250.0 Codeforces Round 1063 Editorial
20247 Souvlaki VS. Kalamaki math sortings Statement A Codeforces Round 1063 (Div. 2) {2163} PROGRAMMING 500.0 Codeforces Round 1063 Editorial
6957 Copy String binary search greedy implementation strings Statement D Codeforces Global Round 30 (Div. 1 + Div. 2) {2164} PROGRAMMING 1750.0 Codeforces Global Round 30 Editorial
873 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
1834 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
6641 Marble Council dp math Statement B Codeforces Round 1064 (Div. 1) {2165} PROGRAMMING 1000.0 148452
19287 Tab Closing math Statement B Codeforces Round 1064 (Div. 2) {2166} PROGRAMMING 750.0 Codeforces Round 1064 (Div. 1, Div. 2) Editorial
9735 khba Loves to Sleep! binary search data structures geometry implementation math Statement E Codeforces Round 1062 (Div. 4) {2167} PROGRAMMING Arpa Video Tutorial
31943 Yet Another Array Problem brute force math number theory Statement D Codeforces Round 1062 (Div. 4) {2167} PROGRAMMING Arpa Video Tutorial
62614 Square? math Statement A Codeforces Round 1062 (Div. 4) {2167} PROGRAMMING Arpa Video Tutorial
3598 Encode and Decode (Hard Version) bitmasks interactive math Statement A2 Testing Round 20 (Unrated, Communication Problems) {2168} PROGRAMMING Testing Round 20 Editorial (officially unofficial)
9112 Removal of a Sequence (Easy Version) binary search bitmasks geometry implementation math number theory Statement D1 Educational Codeforces Round 184 (Rated for Div. 2) {2169} PROGRAMMING Educational Codeforces Round 184 Editorial
2397 Removal of a Sequence (Hard Version) binary search constructive algorithms divide and conquer greedy implementation math number theory probabilities Statement D2 Educational Codeforces Round 184 (Rated for Div. 2) {2169} PROGRAMMING Educational Codeforces Round 184 Editorial
359 Subsequence Problem combinatorics dp fft math Statement F Educational Codeforces Round 184 (Rated for Div. 2) {2169} PROGRAMMING Educational Codeforces Round 184 Editorial
13569 Range Operation math two pointers Statement C Educational Codeforces Round 184 (Rated for Div. 2) {2169} PROGRAMMING Educational Codeforces Round 184 Editorial
20760 Maximum Neighborhood greedy math Statement A Educational Codeforces Round 185 (Rated for Div. 2) {2170} PROGRAMMING Educational Codeforces Round 185 Editorial
15471 Addition on a Segment greedy math Statement B Educational Codeforces Round 185 (Rated for Div. 2) {2170} PROGRAMMING Educational Codeforces Round 185 Editorial
2494 Sakura Adachi and Optimal Sequences bitmasks combinatorics greedy math Statement G Codeforces Round 1065 (Div. 3) {2171} PROGRAMMING Codeforces Round 1065 (Div. 3) Editorial
38621 Shizuku Hoshikawa and Farm Legs math Statement A Codeforces Round 1065 (Div. 3) {2171} PROGRAMMING Codeforces Round 1065 (Div. 3) Editorial
111 Circles Are Far from Each Other Statement C 2025 ICPC Asia Taichung Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2172} PROGRAMMING
140 Divisor Card Game Statement D 2025 ICPC Asia Taichung Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2172} PROGRAMMING
4384 Cluster Computing System Statement F 2025 ICPC Asia Taichung Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2172} PROGRAMMING
900 Kindergarten Homework Statement K 2025 ICPC Asia Taichung Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2172} PROGRAMMING
641 Isla's Memory Thresholds binary search data structures divide and conquer math Statement F Codeforces Round 1068 (Div. 2) {2173} PROGRAMMING 3000.0
3913 Taiga's Carry Chains bitmasks brute force dp greedy Statement D Codeforces Round 1068 (Div. 2) {2173} PROGRAMMING 1750.0
24672 Sleeping Through Classes implementation Statement A Codeforces Round 1068 (Div. 2) {2173} PROGRAMMING 500.0
1649 Shiro's Mirror Duel interactive probabilities Statement E Codeforces Round 1068 (Div. 2) {2173} PROGRAMMING 2250.0
116 Game of Scientists (Version 2) brute force chinese remainder theorem interactive math Statement E2 Codeforces Round 1069 (Div. 1) {2174} PROGRAMMING 1750.0 Codeforces Round 1069 Editorial
161 Game of Scientists (Version 1) chinese remainder theorem interactive math Statement E1 Codeforces Round 1069 (Div. 1) {2174} PROGRAMMING 1750.0 Codeforces Round 1069 Editorial
517 Mosaic Tree combinatorics dp fft math trees Statement F Codeforces Round 1069 (Div. 1) {2174} PROGRAMMING 3500.0 Codeforces Round 1069 Editorial
15479 Needle in a Haystack greedy strings two pointers Statement A Codeforces Round 1069 (Div. 1) {2174} PROGRAMMING 500.0 Codeforces Round 1069 Editorial
1273 Beautiful Patterns (Easy Version) math probabilities Statement C1 Codeforces Round 1069 (Div. 1) {2174} PROGRAMMING 1500.0 Codeforces Round 1069 Editorial
1121 Beautiful Patterns (Hard Version) math probabilities Statement C2 Codeforces Round 1069 (Div. 1) {2174} PROGRAMMING 500.0 Codeforces Round 1069 Editorial
13196 XOR Array math Statement B Codeforces Round 1069 (Div. 2) {2175} PROGRAMMING 750.0 Codeforces Round 1069 Editorial
1594 Omega Numbers bitmasks dp math number theory Statement F Codeforces Round 1070 (Div. 2) {2176} PROGRAMMING 2750.0 Codeforces Round 1070 (Div.2) Editorial
16630 Odd Process greedy math sortings Statement C Codeforces Round 1070 (Div. 2) {2176} PROGRAMMING 1500.0 Codeforces Round 1070 (Div.2) Editorial
26761 Yes or Yes brute force greedy strings Statement A Good Bye 2025 {2178} PROGRAMMING 500.0
22630 Impost or Sus greedy implementation strings Statement B Good Bye 2025 {2178} PROGRAMMING 750.0
14295 Blackslex and Penguin Civilization bitmasks constructive algorithms greedy math Statement D Codeforces Round 1071 (Div. 3) {2179} PROGRAMMING Codeforces Round 1071 (Div. 3) Editorial
1380 Blackslex and Plants bitmasks data structures dp math Statement H Codeforces Round 1071 (Div. 3) {2179} PROGRAMMING Codeforces Round 1071 (Div. 3) Editorial
1321 Blackslex and Penguin Migration brute force interactive math Statement G Codeforces Round 1071 (Div. 3) {2179} PROGRAMMING Codeforces Round 1071 (Div. 3) Editorial
6124 Blackslex and Girls constructive algorithms geometry math Statement E Codeforces Round 1071 (Div. 3) {2179} PROGRAMMING Codeforces Round 1071 (Div. 3) Editorial
23419 Blackslex and Number Theory math number theory sortings sortings Statement C Codeforces Round 1071 (Div. 3) {2179} PROGRAMMING Codeforces Round 1071 (Div. 3) Editorial
35710 Blackslex and Password math strings Statement A Codeforces Round 1071 (Div. 3) {2179} PROGRAMMING Codeforces Round 1071 (Div. 3) Editorial
6803 XOR-factorization bitmasks constructive algorithms dp greedy number theory Statement C Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} PROGRAMMING 1500.0 Codeforces Global Round 31
1815 No Effect XOR bitmasks math Statement E Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} PROGRAMMING 2000.0 Codeforces Global Round 31
156 Balance combinatorics math Statement G Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} PROGRAMMING 2750.0 Codeforces Global Round 31
4424 Insolvable Disks greedy math Statement D Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} PROGRAMMING 1750.0 Codeforces Global Round 31
25328 Ashmal greedy strings Statement B Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} PROGRAMMING 750.0 Codeforces Global Round 31
691 Greta's Game binary search dp math Statement G 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} PROGRAMMING Tutorial
174 Cacti Classification binary search interactive math Statement C 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} PROGRAMMING Tutorial
4111 Alphabet City binary search math strings Statement A 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} PROGRAMMING Tutorial
795 Jinx or Jackpot brute force dp math probabilities Statement J 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} PROGRAMMING Tutorial
155 LLM Training math Statement L 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} PROGRAMMING Tutorial
7540 Honey Cake math number theory Statement H 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} PROGRAMMING Tutorial
9600 Christmas Tree Decoration combinatorics dp greedy math Statement D Educational Codeforces Round 186 (Rated for Div. 2) {2182} PROGRAMMING Educational Codeforces Round 186 Editorial
11363 War Strategy binary search greedy math two pointers Statement C Hello 2026 {2183} PROGRAMMING 1500.0
177 Minimise Cost dp Statement H Hello 2026 {2183} PROGRAMMING 4000.0
3049 LCM is Legendary Counting Master dp math number theory Statement E Hello 2026 {2183} PROGRAMMING 2250.0
23428 Huge Pile binary search math Statement C Codeforces Round 1072 (Div. 3) {2184} PROGRAMMING Codeforces Round 1072 (Div. 3) Editorial
10320 Unfair Game combinatorics dp math Statement D Codeforces Round 1072 (Div. 3) {2184} PROGRAMMING Codeforces Round 1072 (Div. 3) Editorial
40313 Social Experiment math Statement A Codeforces Round 1072 (Div. 3) {2184} PROGRAMMING Codeforces Round 1072 (Div. 3) Editorial
25655 Hourglass math Statement B Codeforces Round 1072 (Div. 3) {2184} PROGRAMMING Codeforces Round 1072 (Div. 3) Editorial
46549 Perfect Root constructive algorithms math Statement A Codeforces Round 1074 (Div. 4) {2185} PROGRAMMING Codeforces Round 1074 (Div. 4) Editorial
3745 Mixing MEXes data structures implementation math Statement G Codeforces Round 1074 (Div. 4) {2185} PROGRAMMING Codeforces Round 1074 (Div. 4) Editorial
22233 OutOfMemoryError data structures implementation math two pointers Statement D Codeforces Round 1074 (Div. 4) {2185} PROGRAMMING Codeforces Round 1074 (Div. 4) Editorial
723 Cool Problem bitmasks brute force divide and conquer dp math Statement D Codeforces Round 1077 (Div. 1) {2187} PROGRAMMING 2000.0 Codeforces Round 1077 (Div. 1, Div. 2) Editorial
22506 Seats greedy Statement B Codeforces Round 1077 (Div. 2) {2188} PROGRAMMING 1000.0 Codeforces Round 1077 (Div. 1, Div. 2) Editorial
2101 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
14896 XOR Convenience (Easy Version) bitmasks brute force constructive algorithms math Statement C1 Codeforces Round 1075 (Div. 2) {2189} PROGRAMMING 1250.0 Codeforces Round 1075 (Div. 2) Editorial
6600 XOR-convenience (Hard Version) bitmasks brute force constructive algorithms math Statement C2 Codeforces Round 1075 (Div. 2) {2189} PROGRAMMING 750.0 Codeforces Round 1075 (Div. 2) Editorial
4296 Little String (Easy Version) combinatorics dp math Statement D1 Codeforces Round 1075 (Div. 2) {2189} PROGRAMMING 2000.0 Codeforces Round 1075 (Div. 2) Editorial
909 Majority Wins? dp greedy math strings Statement E Codeforces Round 1075 (Div. 2) {2189} PROGRAMMING 2500.0 Codeforces Round 1075 (Div. 2) Editorial
16462 The Curse of the Frog greedy math Statement B Codeforces Round 1075 (Div. 2) {2189} PROGRAMMING 1000.0 Codeforces Round 1075 (Div. 2) Editorial
18533 Sorting Game games greedy Statement A Codeforces Round 1073 (Div. 1) {2190} PROGRAMMING 500.0 Codeforces Round 1073 (Div. 1, Div. 2) Editorial
108 Maximize Determinant graphs Statement G Codeforces Round 1073 (Div. 1) {2190} PROGRAMMING 3750.0 Codeforces Round 1073 (Div. 1, Div. 2) Editorial
12409 All-in-one Gun binary search greedy math Statement C Codeforces Round 1081 (Div. 2) {2192} PROGRAMMING 1250.0 Codeforces Round 1081 (Div. 2) Editorial
204 Fish Fight dp math probabilities Statement F Codeforces Round 1081 (Div. 2) {2192} PROGRAMMING 3000.0 Codeforces Round 1081 (Div. 2) Editorial
44842 DBMB and the Array brute force math Statement A Codeforces Round 1076 (Div. 3) {2193} PROGRAMMING Разбор Codeforces Round 1076 (Div. 3)
16469 Product Queries dp math number theory Statement E Codeforces Round 1076 (Div. 3) {2193} PROGRAMMING Разбор Codeforces Round 1076 (Div. 3)
11832 Secret message bitmasks math Statement C Codeforces Round 1078 (Div. 2) {2194} PROGRAMMING 1750.0 Codeforces Round #1078 Editorial
20231 Offshores greedy implementation math Statement B Codeforces Round 1078 (Div. 2) {2194} PROGRAMMING 1000.0 Codeforces Round #1078 Editorial
25280 Lawn Mower math Statement A Codeforces Round 1078 (Div. 2) {2194} PROGRAMMING 500.0 Codeforces Round #1078 Editorial
2985 Parabola Independence dp graphs math Statement F Codeforces Round 1080 (Div. 3) {2195} PROGRAMMING Codeforces Round 1080 (Div. 3) Editorial
38284 Sieve of Erato67henes math Statement A Codeforces Round 1080 (Div. 3) {2195} PROGRAMMING Codeforces Round 1080 (Div. 3) Editorial
15053 Absolute Cinema math Statement D Codeforces Round 1080 (Div. 3) {2195} PROGRAMMING Codeforces Round 1080 (Div. 3) Editorial
317 Fuzzy Concatenation (Easy Version) binary search bitmasks brute force data structures greedy string suffix structures Statement E1 Codeforces Round 1079 (Div. 1) {2196} PROGRAMMING 2000.0 Tutorial
246 Fuzzy Concatenation (Hard version) binary search data structures dp greedy string suffix structures Statement E2 Codeforces Round 1079 (Div. 1) {2196} PROGRAMMING 1000.0 Tutorial
9550 Another Problem about Beautiful Pairs brute force math two pointers Statement B Codeforces Round 1079 (Div. 1) {2196} PROGRAMMING 750.0 Tutorial
1090 Double Bracket Sequence data structures dp greedy sortings Statement D Codeforces Round 1079 (Div. 1) {2196} PROGRAMMING 2250.0 Tutorial
17731 Game with a Fraction games math Statement A Codeforces Round 1079 (Div. 1) {2196} PROGRAMMING 500.0 Tutorial
24239 Friendly Numbers brute force math Statement A Codeforces Round 1079 (Div. 2) {2197} PROGRAMMING 500.0
104 Sum of MEX *special combinatorics data structures dp math Statement H Kotlin Heroes: Episode 14 {2199} PROGRAMMING 151783
183 Self-Produced Sequences *special combinatorics math Statement F Kotlin Heroes: Episode 14 {2199} PROGRAMMING 151783
1244 Two Towers *special greedy math Statement B Kotlin Heroes: Episode 14 {2199} PROGRAMMING 151783
335 Two Arrays *special math Statement D Kotlin Heroes: Episode 14 {2199} PROGRAMMING 151783
66 Jammer *special math Statement G Kotlin Heroes: Episode 14 {2199} PROGRAMMING 151783
1266 Operation Permutation combinatorics dp math probabilities Statement G Codeforces Round 1084 (Div. 3) {2200} PROGRAMMING Codeforces Round 1084 (Div. 3) Editorial
546 Six Seven divide and conquer math number theory strings trees Statement H Codeforces Round 1084 (Div. 3) {2200} PROGRAMMING Codeforces Round 1084 (Div. 3) Editorial
9508 Divisive Battle games greedy math number theory Statement E Codeforces Round 1084 (Div. 3) {2200} PROGRAMMING Codeforces Round 1084 (Div. 3) Editorial
13729 Portal greedy sortings Statement D Codeforces Round 1084 (Div. 3) {2200} PROGRAMMING Codeforces Round 1084 (Div. 3) Editorial
2259 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
81 Codeforces Heuristic Contest 1001 constructive algorithms Statement G Codeforces Round 1082 (Div. 1) {2201} PROGRAMMING 5000.0 Codeforces Round 1082 (Div. 1, Div. 2) Complete Editorial
306 ABBA Counting fft math number theory strings Statement E Codeforces Round 1082 (Div. 1) {2201} PROGRAMMING 3000.0 Codeforces Round 1082 (Div. 1, Div. 2) Complete Editorial
17600 Parkour Design math Statement A Codeforces Round 1082 (Div. 2) {2202} PROGRAMMING 750.0 Codeforces Round 1082 (Div. 1, Div. 2) Complete Editorial
8141 Test Generator binary search bitmasks greedy math Statement C Educational Codeforces Round 187 (Rated for Div. 2) {2203} PROGRAMMING Educational Codeforces Round 187 Editorial
1549 Probabilistic Card Game binary search data structures math ternary search Statement E Educational Codeforces Round 187 (Rated for Div. 2) {2203} PROGRAMMING Educational Codeforces Round 187 Editorial
472 Binary Search with One Swap binary search divide and conquer dp hashing math Statement F Educational Codeforces Round 187 (Rated for Div. 2) {2203} PROGRAMMING Educational Codeforces Round 187 Editorial
16647 Beautiful Numbers dp greedy math Statement B Educational Codeforces Round 187 (Rated for Div. 2) {2203} PROGRAMMING Educational Codeforces Round 187 Editorial
20106 Towers of Boxes math Statement A Educational Codeforces Round 187 (Rated for Div. 2) {2203} PROGRAMMING Educational Codeforces Round 187 Editorial
1379 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
5311 Sum of Digits (and Again) brute force constructive algorithms math Statement E Educational Codeforces Round 188 (Rated for Div. 2) {2204} PROGRAMMING Educational Codeforces Round 188 Editorial
20064 Spring math Statement C Educational Codeforces Round 188 (Rated for Div. 2) {2204} PROGRAMMING Educational Codeforces Round 188 Editorial
17756 Simons and Cakes for Success implementation math Statement B Codeforces Round 1083 (Div. 2) {2205} PROGRAMMING 750.0 Tutorial
820 Upside Down Dijkstra dfs and similar Statement C 2026 ICPC Asia Pacific Championship - Online Mirror (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2206} PROGRAMMING Tutorial (PDF)
994 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
15148 1-1 greedy strings Statement A Codeforces Round 1085 (Div. 1 + Div. 2) {2207} PROGRAMMING 750.0 Codeforces Round 1085 (Div. 1 + Div. 2) Editorial
22267 Bingo Candies constructive algorithms math Statement A Codeforces Round 1086 (Div. 2) {2208} PROGRAMMING 500.0 Tutorial
12906 Stamina and Tasks dp greedy math Statement C Codeforces Round 1086 (Div. 2) {2208} PROGRAMMING 1250.0 Tutorial
277 A Simple Problem binary search greedy math trees Statement F Codeforces Round 1089 (Div. 2) {2210} PROGRAMMING 3500.0 Codeforces Round 1089 (Div. 2) Editorial
388 Binary Strings are Simple? constructive algorithms dsu interactive number theory Statement E Codeforces Round 1089 (Div. 2) {2210} PROGRAMMING 2750.0 Codeforces Round 1089 (Div. 2) Editorial
2446 A Simple GCD Problem (Hard Version) dp greedy number theory Statement C2 Codeforces Round 1089 (Div. 2) {2210} PROGRAMMING 1000.0 Codeforces Round 1089 (Div. 2) Editorial
14873 A Simple GCD Problem (Easy Version) greedy number theory Statement C1 Codeforces Round 1089 (Div. 2) {2210} PROGRAMMING 1250.0 Codeforces Round 1089 (Div. 2) Editorial
126 Median Deletion Statement H Nebius Round 2 (Codeforces Round 1088, Div. 1 + Div. 2) {2211} PROGRAMMING 4000.0 Nebius Round 2 and Codeforces Round 1088 Editorial
3371 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
13192 Mickey Mouse Constructive greedy math Statement B Nebius Round 2 (Codeforces Round 1088, Div. 1 + Div. 2) {2211} PROGRAMMING 1250.0 Nebius Round 2 and Codeforces Round 1088 Editorial
17963 Antimedian Deletion implementation math Statement A Nebius Round 2 (Codeforces Round 1088, Div. 1 + Div. 2) {2211} PROGRAMMING 500.0 Nebius Round 2 and Codeforces Round 1088 Editorial
6945 Are You Smiling? *special Statement B April Fools Day Contest 2026 {2214} PROGRAMMING April Fools Day Contest 2026 Editorial
1332 RReeppeettiittiioonn binary search brute force implementation math number theory Statement B Codeforces Round 1092 (Unrated, Div. 1, Based on THUPC 2026 — Finals) {2215} PROGRAMMING 1250.0 152930
3945 Interval Mod constructive algorithms dp greedy math Statement A Codeforces Round 1092 (Unrated, Div. 1, Based on THUPC 2026 — Finals) {2215} PROGRAMMING 750.0 152930
921 Interval Game bitmasks combinatorics dp games greedy math probabilities Statement F Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} PROGRAMMING 2750.0 Tutorial
3869 Flip the Bit (Hard Version) greedy implementation math Statement D Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} PROGRAMMING 1500.0 Tutorial
12194 Grid Covering math number theory Statement C Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} PROGRAMMING 1500.0 Tutorial
43620 The 67th Integer Problem brute force games implementation math Statement A Codeforces Round 1090 (Div. 4) {2218} PROGRAMMING Codeforces Round 1090 (Div. 4) Editorial
31664 The 67th Permutation Problem constructive algorithms greedy math Statement C Codeforces Round 1090 (Div. 4) {2218} PROGRAMMING Codeforces Round 1090 (Div. 4) Editorial
4736 The 67th Iteration of "Counting is Fun" dfs and similar implementation math Statement G Codeforces Round 1090 (Div. 4) {2218} PROGRAMMING Codeforces Round 1090 (Div. 4) Editorial
41391 The 67th 6-7 Integer Problem greedy math Statement B Codeforces Round 1090 (Div. 4) {2218} PROGRAMMING Codeforces Round 1090 (Div. 4) Editorial
22227 The 67th OEIS Problem greedy math number theory Statement D Codeforces Round 1090 (Div. 4) {2218} PROGRAMMING Codeforces Round 1090 (Div. 4) Editorial
551 MEX Replacement on Tree Statement D Codeforces Round 1093 (Div. 1) {2219} PROGRAMMING 2250.0 Codeforces Round 1093 (Div. 1, Div. 2) Editorial
3871 Unique Values (Hard version) binary search constructive algorithms divide and conquer interactive math Statement B2 Codeforces Round 1093 (Div. 1) {2219} PROGRAMMING 500.0 Codeforces Round 1093 (Div. 1, Div. 2) Editorial
11072 Grid L brute force math number theory Statement A Codeforces Round 1093 (Div. 1) {2219} PROGRAMMING 500.0 Codeforces Round 1093 (Div. 1, Div. 2) Editorial
161 Weird Chessboard constructive algorithms math Statement E Codeforces Round 1093 (Div. 1) {2219} PROGRAMMING 3000.0 Codeforces Round 1093 (Div. 1, Div. 2) Editorial
2425 Seek the Truth binary search bitmasks interactive Statement E Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) {2222} PROGRAMMING 2250.0 Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) Editorial
748 Building Tree divide and conquer dsu graphs implementation Statement F Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) {2222} PROGRAMMING 3000.0 Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) Editorial
12562 A Wonderful Contest math Statement A Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) {2222} PROGRAMMING 500.0 Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) Editorial
955 Zhily and Signpost binary search chinese remainder theorem dfs and similar math number theory trees Statement C Codeforces Round 1097 (Div. 1, Based on Zhili Cup 2026) {2223} PROGRAMMING 1500.0 Codeforces Round 1097 (Div. 1, Div2, Based on Zhili Cup 2026) Tutorial
3914 Zhily and Barknights binary search data structures dp math sortings two pointers Statement B Codeforces Round 1097 (Div. 1, Based on Zhili Cup 2026) {2223} PROGRAMMING 750.0 Codeforces Round 1097 (Div. 1, Div2, Based on Zhili Cup 2026) Tutorial