Problemset - Codeforces

→ Pay attention

Before contest
Helvetic Coding Contest 2024 online mirror (teams allowed, unrated)
16:12:32
Register now »

→ Filter Problems

Difficulty: —

combinatorics

Add tag

Problems

#	Name
1967E2	Again Counting Arrays (Hard Version) combinatorics, dp		x33
1967E1	Again Counting Arrays (Easy Version) combinatorics, dp, fft, math		x86
1967C	Fenwick Tree brute force, combinatorics, data structures, dp, math, matrices, trees		x978
1957E	Carousel of Combinations brute force, combinatorics, dp, math, number theory	2400	x906
1957C	How Does the Rook Move? combinatorics, dp, math	1600	x6971
1954F	Unique Strings combinatorics, dp, math	3100	x192
1954D	Colored Balls combinatorics, dp, math, sortings	1800	x4674
1952E	Sweep Line combinatorics, games, math		x206
1951G	Clacking Balls combinatorics, math, probabilities	3100	x239
1948F	Rare Coins combinatorics, math, probabilities	2500	x1107
1946E	Girl Permutation combinatorics, dp, math, number theory	2200	x2051
1943D2	Counting Is Fun (Hard Version) combinatorics, dp	2800	x570
1943D1	Counting Is Fun (Easy Version) brute force, combinatorics, dp, math	2400	x1210
1942G	Bessie and Cards combinatorics, dp, math	2800	x360
1942E	Farm Game combinatorics, games	2300	x1417
1935D	Exam in MAC binary search, combinatorics, implementation, math	1800	x7259
1933G	Turtle Magic: Royal Turtle Shell Pattern bitmasks, brute force, combinatorics, constructive algorithms, dfs and similar, math	2300	x855
1931G	One-Dimensional Puzzle combinatorics, math, number theory	2000	x2425
1931F	Chat Screenshots combinatorics, dfs and similar, graphs	1700	x6885
1931D	Divisible Pairs combinatorics, math, number theory	1300	x15705
1930I	Counting Is Fun combinatorics	3500	x49
1930E	2..3...4.... Wonderful! Wonderful! combinatorics, dp, math	2400	x979
1929F	Sasha and the Wedding Binary Search Tree brute force, combinatorics, data structures, dfs and similar, math, trees	2300	x1611
1929D	Sasha and a Walk in the City combinatorics, dp, math, trees	1900	x4132
1928F	Digital Patterns combinatorics, data structures, implementation, math	2900	x209
1925D	Good Trip combinatorics, dp, math, probabilities	1900	x3197
1924E	Paper Cutting Again combinatorics, probabilities	3100	x386
1924D	Balanced Subsequences combinatorics, dp, math	2700	x758
1922B	Forming Triangles combinatorics, constructive algorithms, math, sortings	1200	x18943
1920E	Counting Binary Strings combinatorics, dp, math	2100	x2343
1919E	Counting Prefixes combinatorics, constructive algorithms, dp, implementation, math	2600	x771
1917D	Yet Another Inversions Problem combinatorics, data structures, dp, implementation, math, number theory	2300	x1651
1917B	Erase First or Second Letter brute force, combinatorics, data structures, dp, strings	1100	x19288
1916H2	Matrix Rank (Hard Version) combinatorics, dp, math, matrices, string suffix structures	2700	x501
1916H1	Matrix Rank (Easy Version) brute force, combinatorics, dp, math, matrices	2700	x583
1914G2	Light Bulbs (Hard Version) combinatorics, data structures, dfs and similar, dp, graphs, hashing	2300	x1212
1914G1	Light Bulbs (Easy Version) brute force, combinatorics, dfs and similar, dp, dsu, graphs, math, trees	2100	x1661
1912K	Kim's Quest bitmasks, combinatorics, dp	1800	x2008
1912B	Blueprint for Seating combinatorics, divide and conquer, math	2100	x918
1910I	Inverse Problem *special problem, combinatorics, dp	2700	x39
1909I	Short Permutation Problem combinatorics, dp, fft, math	1900	x73
1909F2	Small Permutation Problem (Hard Version) combinatorics, dp, math	2500	x825
1909F1	Small Permutation Problem (Easy Version) brute force, combinatorics, dp, math	2200	x1630
1907E	Good Triples brute force, combinatorics, number theory	1600	x8741
1906J	Count BFS Graph combinatorics, dp	2100	x625
1906H	Twin Friends combinatorics, dp	2200	x601
1905E	One-X combinatorics, dfs and similar, dp, math, trees	2400	x844
1895F	Fancy Arrays combinatorics, dp, math, matrices	2600	x623
1893E	Cacti Symphony combinatorics, dfs and similar, dp, graphs	3500	x179
1886D	Monocarp and the Set combinatorics, data structures, math	2100	x3311
1879D	Sum of XOR Functions bitmasks, combinatorics, divide and conquer, dp, math	1700	x6556
1879C	Make it Alternating combinatorics, dp, greedy	1300	x14855
1876D	Lexichromatography combinatorics, dfs and similar, dsu, graphs, two pointers	2500	x810
1876B	Effects of Anti Pimples combinatorics, number theory, sortings	1500	x7469
1868C	Travel Plan combinatorics, dp, implementation, math, trees	2400	x1067
1866M	Mighty Rock Tower brute force, combinatorics, dp, math, probabilities	2400	x687
1866H	Happy Sets combinatorics	2100	x1518
1866B	Battling with Numbers combinatorics, math, number theory	1400	x7172
1864G	Magic Square combinatorics, constructive algorithms, implementation	3100	x252
1863G	Swaps combinatorics, dp, graphs, math	2800	x555
1862D	Ice Cream Balls binary search, combinatorics, constructive algorithms, math	1300	x15974
1861E	Non-Intersecting Subpermutations combinatorics, dp, implementation, math	2300	x1608
1857G	Counting Graphs combinatorics, divide and conquer, dsu, graphs, greedy, sortings, trees	2000	x4066
1855B	Longest Divisors Interval brute force, combinatorics, greedy, math, number theory	900	x23667
1854C	Expected Destruction combinatorics, dp, math, probabilities	2500	x1390
1850G	The Morning Star combinatorics, data structures, geometry, implementation, math, sortings	1500	x11162
1848F	Vika and Wiki binary search, bitmasks, combinatorics, divide and conquer, dp, math	2400	x1447
1847E	Triangle Platinum? brute force, combinatorics, implementation, interactive, math, probabilities	2900	x315
1844H	Multiple of Three Cycles combinatorics, data structures, dp, dsu, math	3400	x130
1843D	Apple Tree combinatorics, dfs and similar, dp, math, trees	1200	x16999
1843C	Sum in Binary Tree bitmasks, combinatorics, math, trees	800	x31015
1842G	Tenzing and Random Operations combinatorics, dp, math, probabilities	2800	x921
1840C	Ski Resort combinatorics, math, two pointers	1000	x24509
1840B	Binary Cafe bitmasks, combinatorics, math	1100	x21470
1838E	Count Supersequences combinatorics, dp, math	2500	x1368
1837E	Playoff Fixing combinatorics, trees	2200	x2094
1835E	Old Mobile combinatorics, dp, probabilities	3500	x202
1833F	Ira and Flamenco combinatorics, constructive algorithms, data structures, implementation, math, sortings, two pointers	1700	x6648
1832E	Combinatorics Problem brute force, combinatorics, dp	2200	x2054
1830C	Hyperregular Bracket Strings combinatorics, greedy, hashing, math, number theory, sortings	2400	x1519
1829H	Don't Blame Me bitmasks, combinatorics, dp, math	1700	x7029
1827A	Counting Orders combinatorics, math, sortings, two pointers	1100	x17415
1824B2	LuoTianyi and the Floating Islands (Hard Version) combinatorics, dfs and similar, math, probabilities, trees	2300	x2489
1824B1	LuoTianyi and the Floating Islands (Easy Version) combinatorics, math, probabilities, trees	1800	x4322
1823A	A-characteristic combinatorics, constructive algorithms, math	800	x15785
1821F	Timber combinatorics, dp, fft, math	2600	x703
1821A	Matching combinatorics, math	800	x19343
1817C	Similar Polynomials combinatorics, math	2400	x919
1815D	XOR Counting bitmasks, combinatorics, dp, math	2600	x1031
1811G2	Vlad and the Nice Paths (hard version) binary search, combinatorics, data structures, dp, math, two pointers	2200	x1613
1811G1	Vlad and the Nice Paths (easy version) combinatorics, dp, math	2100	x1906
1810H	Last Number combinatorics, math	2900	x129
1809G	Prediction combinatorics, dp, math	2800	x410
1808E3	Minibuses on Venus (hard version) brute force, combinatorics, dp, math	2800	x417
1808E2	Minibuses on Venus (medium version) combinatorics, divide and conquer, dp, matrices	2500	x645
1808E1	Minibuses on Venus (easy version) combinatorics, divide and conquer, dp	2200	x1249
1806D	DSU Master combinatorics, dp, dsu, math	2500	x844
1799G	Count Voting combinatorics, dp, math	2600	x696
1795D	Triangle Coloring combinatorics, math	1600	x8442
1794D	Counting Factorizations combinatorics, divide and conquer, dp, math, number theory	1900	x3339

←