Problemset - Codeforces

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combinatorics

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Problems

#	Name
2038F	Alternative Platforms combinatorics, data structures, fft, math, sortings	2500	x264
2037G	Natlan Exploring bitmasks, combinatorics, data structures, dp, math, number theory	2000	x1704
2032F	Peanuts combinatorics, dp, games, math	2700	x253
2030G2	The Destruction of the Universe (Hard Version) combinatorics, math	3100	x109
2030G1	The Destruction of the Universe (Easy Version) combinatorics, greedy, math	2900	x147
2030E	MEXimize the Score combinatorics, data structures, dp, greedy, implementation, math	2200	x1310
2030B	Minimise Oneness combinatorics, constructive algorithms, games, math	800	x19932
2029H	Message Spread bitmasks, brute force, combinatorics, dp	3500	x38
2028E	Alice's Adventures in the Rabbit Hole combinatorics, dfs and similar, dp, games, greedy, math, probabilities, trees	2300	x1070
2025E	Card Game combinatorics, dp, fft, greedy, math	2200	x1744
2025B	Binomial Coefficients, Kind Of combinatorics, dp, math	1100	x16374
2022E2	Billetes MX (Hard Version) binary search, combinatorics, data structures, dsu, graphs	2600	x371
2022E1	Billetes MX (Easy Version) 2-sat, binary search, combinatorics, constructive algorithms, dfs and similar, dsu, graphs	2500	x409
2018F1	Speedbreaker Counting (Easy Version) combinatorics, dp, greedy, math	2900	x208
2008F	Sakurako's Box combinatorics, math, number theory	1400	x12483
2006F	Dora's Paint brute force, combinatorics, constructive algorithms, graphs, implementation	3500	x118
2005A	Simple Palindrome combinatorics, constructive algorithms, greedy, math	900	x21613
2001E2	Deterministic Heap (Hard Version) combinatorics, dp, trees	2900	x223
2001E1	Deterministic Heap (Easy Version) combinatorics, dp, math, trees	2400	x1274
2000E	Photoshoot for Gorillas combinatorics, data structures, greedy, math	1400	x13261
1999F	Expected Median combinatorics, math	1500	x10397
1997F	Chips on a Line brute force, combinatorics, dp, greedy, math	2700	x901
1996E	Decode combinatorics, data structures, implementation, math	1600	x9812
1996D	Fun binary search, brute force, combinatorics, math, number theory	1500	x15982
1994H	Fortnite combinatorics, constructive algorithms, games, greedy, hashing, interactive, math, number theory, strings	3500	x706
1992G	Ultra-Meow combinatorics, dp, math	2000	x3139
1989E	Distance to Different combinatorics, dp, math	2300	x1992
1988F	Heartbeat combinatorics, dp, fft, math	3000	x214
1986G1	Permutation Problem (Simple Version) binary search, brute force, combinatorics, data structures, math, number theory	2200	x1498
1985G	D-Function combinatorics, math, number theory	1600	x9443
1985E	Secret Box brute force, combinatorics, math	1200	x19969
1984H	Tower Capturing combinatorics, dp, geometry	3300	x169
1984C2	Magnitude (Hard Version) combinatorics, dp, greedy, math	1700	x7435
1983E	I Love Balls combinatorics, math, probabilities	2300	x2018
1982E	Number of k-good subarrays bitmasks, brute force, combinatorics, divide and conquer, dp, math, meet-in-the-middle	2300	x1602
1979C	Earning on Bets binary search, combinatorics, constructive algorithms, number theory	1200	x18824
1976E	Splittable Permutations combinatorics, data structures, dfs and similar, greedy, math, trees	2500	x1045
1976D	Invertible Bracket Sequences binary search, combinatorics, data structures, divide and conquer, implementation, two pointers	2000	x4635
1975F	Set bitmasks, brute force, combinatorics, dfs and similar, divide and conquer, dp, math	2600	x833
1974C	Beautiful Triple Pairs combinatorics, data structures	1400	x15829
1967E2	Again Counting Arrays (Hard Version) combinatorics, dp, math	3500	x103
1967E1	Again Counting Arrays (Easy Version) combinatorics, dp, fft, math	3100	x217
1967C	Fenwick Tree bitmasks, brute force, combinatorics, data structures, dp, math, trees	2300	x1783
1958F	Narrow Paths *special problem, combinatorics	2000	x193
1957E	Carousel of Combinations brute force, combinatorics, dp, math, number theory	2400	x1280
1957C	How Does the Rook Move? combinatorics, dp, math	1600	x9728
1954F	Unique Strings combinatorics, dp, math	3100	x256
1954D	Colored Balls combinatorics, dp, math, sortings	1800	x6241
1952E	Sweep Line combinatorics, games, math		x258
1951G	Clacking Balls combinatorics, math, probabilities	3100	x337
1948F	Rare Coins combinatorics, math, probabilities	2500	x1337
1946E	Girl Permutation combinatorics, dp, math, number theory	2200	x2580
1943D2	Counting Is Fun (Hard Version) combinatorics, dp	2800	x808
1943D1	Counting Is Fun (Easy Version) brute force, combinatorics, dp, math	2400	x1513
1942G	Bessie and Cards combinatorics, dp, math	2800	x456
1942E	Farm Game combinatorics, games	2300	x1696
1935D	Exam in MAC binary search, combinatorics, implementation, math	1800	x8319
1933G	Turtle Magic: Royal Turtle Shell Pattern bitmasks, brute force, combinatorics, constructive algorithms, dfs and similar, math	2300	x987
1931G	One-Dimensional Puzzle combinatorics, math, number theory	2000	x2877
1931F	Chat Screenshots combinatorics, dfs and similar, graphs	1700	x8169
1931D	Divisible Pairs combinatorics, math, number theory	1300	x19277
1930I	Counting Is Fun combinatorics	3500	x74
1930E	2..3...4.... Wonderful! Wonderful! combinatorics, dp, math	2400	x1153
1929F	Sasha and the Wedding Binary Search Tree brute force, combinatorics, data structures, dfs and similar, math, trees	2300	x1821
1929D	Sasha and a Walk in the City combinatorics, dp, math, trees	1900	x4856
1928F	Digital Patterns combinatorics, data structures, implementation, math	2900	x244
1925D	Good Trip combinatorics, dp, math, probabilities	1900	x3700
1924E	Paper Cutting Again combinatorics, probabilities	3100	x441
1924D	Balanced Subsequences combinatorics, dp, math	2700	x1026
1922B	Forming Triangles combinatorics, constructive algorithms, math, sortings	1200	x20830
1920E	Counting Binary Strings combinatorics, dp, math	2100	x2759
1919E	Counting Prefixes combinatorics, constructive algorithms, dp, implementation, math	2600	x886
1917D	Yet Another Inversions Problem combinatorics, data structures, dp, implementation, math, number theory	2300	x1809
1917B	Erase First or Second Letter brute force, combinatorics, data structures, dp, strings	1100	x22808
1916H2	Matrix Rank (Hard Version) combinatorics, dp, math, matrices, string suffix structures	2700	x539
1916H1	Matrix Rank (Easy Version) brute force, combinatorics, dp, math, matrices	2700	x616
1914G2	Light Bulbs (Hard Version) combinatorics, data structures, dfs and similar, dp, graphs, hashing	2300	x1413
1914G1	Light Bulbs (Easy Version) brute force, combinatorics, dfs and similar, dp, dsu, graphs, math, trees	2100	x1926
1912K	Kim's Quest bitmasks, combinatorics, dp	1800	x2561
1912B	Blueprint for Seating combinatorics, divide and conquer, math	2100	x1100
1910I	Inverse Problem *special problem, combinatorics, dp	2700	x50
1909I	Short Permutation Problem combinatorics, dp, fft, math	1900	x119
1909F2	Small Permutation Problem (Hard Version) combinatorics, dp, math	2500	x952
1909F1	Small Permutation Problem (Easy Version) brute force, combinatorics, dp, math	2200	x1854
1907E	Good Triples brute force, combinatorics, number theory	1600	x10491
1906J	Count BFS Graph combinatorics, dp	2100	x827
1906H	Twin Friends combinatorics, dp	2200	x752
1905E	One-X combinatorics, dfs and similar, dp, math, trees	2400	x1008
1895F	Fancy Arrays combinatorics, dp, math, matrices	2600	x773
1893E	Cacti Symphony combinatorics, dfs and similar, dp, graphs	3500	x198
1886D	Monocarp and the Set combinatorics, data structures, math	2100	x3630
1879D	Sum of XOR Functions bitmasks, combinatorics, divide and conquer, dp, math	1700	x7568
1879C	Make it Alternating combinatorics, dp, greedy	1300	x17377
1876D	Lexichromatography combinatorics, dfs and similar, dsu, graphs, two pointers	2500	x892
1876B	Effects of Anti Pimples combinatorics, number theory, sortings	1500	x8443
1868C	Travel Plan combinatorics, dp, implementation, math, trees	2400	x1177
1866M	Mighty Rock Tower brute force, combinatorics, dp, math, probabilities	2400	x820
1866H	Happy Sets combinatorics	2100	x1668
1866B	Battling with Numbers combinatorics, math, number theory	1400	x7839
1864G	Magic Square combinatorics, constructive algorithms, implementation	3100	x280

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