Problemset - Codeforces

→ Pay attention

Before contest
Educational Codeforces Round 165 (Rated for Div. 2)
43:05:22
Register now »

→ Filter Problems

Difficulty: —

number theory

Add tag

Problems

#	Name
1718B	Fibonacci Strings greedy, implementation, math, number theory	2000	x2871
1254B2	Send Boxes to Alice (Hard Version) constructive algorithms, greedy, math, number theory, ternary search, two pointers	2100	x2929
359C	Prime Number math, number theory	1900	x2932
822D	My pretty girl Noora brute force, dp, greedy, math, number theory	1800	x2953
354C	Vasya and Beautiful Arrays brute force, dp, number theory	2100	x2968
900D	Unusual Sequences bitmasks, combinatorics, dp, math, number theory	2000	x2969
803F	Coprime Subsequences bitmasks, combinatorics, number theory	2000	x2983
1327D	Infinite Path brute force, dfs and similar, graphs, math, number theory	2200	x3023
66D	Petya and His Friends constructive algorithms, math, number theory	1700	x3042
959D	Mahmoud and Ehab and another array construction task constructive algorithms, greedy, math, number theory	1900	x3044
1955G	GCD on a grid brute force, dfs and similar, dp, implementation, math, number theory	1900	x3092
225B	Well-known Numbers binary search, greedy, number theory	1600	x3098
1389E	Calendar Ambiguity math, number theory	2200	x3107
1419E	Decryption constructive algorithms, implementation, math, number theory	2100	x3137
446C	DZY Loves Fibonacci Numbers data structures, math, number theory	2400	x3170
1673D	Lost Arithmetic Progression combinatorics, math, number theory	1900	x3186
665D	Simple Subset constructive algorithms, greedy, number theory	1800	x3196
1210C	Kamil and Making a Stream math, number theory, trees	2000	x3201
451E	Devu and Flowers bitmasks, combinatorics, number theory	2300	x3214
963A	Alternating Sum math, number theory	1800	x3220
893E	Counting Arrays combinatorics, dp, math, number theory	2000	x3255
498C	Array and Operations flows, graph matchings, number theory	2100	x3272
1762D	GCD Queries constructive algorithms, interactive, number theory	2100	x3276
1025D	Recovering BST brute force, dp, math, number theory, trees	2100	x3294
1794D	Counting Factorizations combinatorics, divide and conquer, dp, math, number theory	1900	x3335
632D	Longest Subsequence brute force, math, number theory	2100	x3363
842C	Ilya And The Tree dfs and similar, graphs, math, number theory, trees	2000	x3410
123A	Prime Permutation implementation, number theory, strings	1300	x3511
566F	Clique in the Divisibility Graph dp, math, number theory	1500	x3516
111B	Petya and Divisors binary search, data structures, number theory	1900	x3535
1468F	Full Turn geometry, hashing, number theory	1700	x3585
55D	Beautiful numbers dp, number theory	2500	x3590
1614D1	Divan and Kostomuksha (easy version) dp, number theory	2100	x3647
1900D	Small GCD bitmasks, brute force, dp, math, number theory	2000	x3668
1107D	Compression dp, implementation, math, number theory	1800	x3672
1665D	GCD Guess bitmasks, chinese remainder theorem, constructive algorithms, games, interactive, math, number theory	2000	x3677
1759F	All Possible Digits binary search, data structures, greedy, math, number theory	1800	x3679
1220D	Alex and Julian bitmasks, math, number theory	1900	x3684
1878F	Vasilije Loves Number Theory brute force, math, number theory	1900	x3686
294C	Shaass and Lights combinatorics, number theory	1900	x3709
615D	Multipliers math, number theory	2000	x3782
439C	Devu and Partitioning of the Array brute force, constructive algorithms, implementation, number theory	1700	x3795
1333F	Kate and imperfection greedy, implementation, math, number theory, sortings, two pointers	2200	x3906
1909D	Split Plus K greedy, math, number theory	1900	x3942
401D	Roman and Numbers bitmasks, brute force, combinatorics, dp, number theory	2000	x3965
27E	Number With The Given Amount Of Divisors brute force, dp, number theory	2000	x3982
177B1	Rectangular Game number theory	1000	x3988
1144E	Median String bitmasks, math, number theory, strings	1900	x4016
1056B	Divide Candies math, number theory	1600	x4065
1516D	Cut binary search, data structures, dp, graphs, number theory, two pointers	2100	x4083
792C	Divide by Three dp, greedy, math, number theory	2000	x4177
1188B	Count Pairs math, matrices, number theory, two pointers	2300	x4208
7C	Line math, number theory	1800	x4225
154B	Colliders math, number theory	1600	x4227
678D	Iterated Linear Function math, number theory	1700	x4262
626C	Block Towers brute force, greedy, math, number theory	1600	x4286
1812D	Trivial Conjecture *special problem, constructive algorithms, math, number theory		x4332
894B	Ralph And His Magic Field combinatorics, constructive algorithms, math, number theory	1800	x4371
1101D	GCD Counting data structures, dfs and similar, dp, number theory, trees	2000	x4392
1254B1	Send Boxes to Alice (Easy Version) constructive algorithms, greedy, math, number theory, ternary search, two pointers	1800	x4408
1195D2	Submarine in the Rybinsk Sea (hard edition) combinatorics, math, number theory	1800	x4411
1632D	New Year Concert binary search, data structures, greedy, math, number theory, two pointers	2000	x4455
16C	Monitor binary search, number theory	1800	x4490
1579F	Array Stabilization (AND version) brute force, graphs, math, number theory, shortest paths	1700	x4561
1558B	Up the Strip brute force, dp, math, number theory, two pointers	1900	x4599
1010C	Border number theory	1800	x4647
1423K	Lonely Numbers binary search, math, number theory, two pointers	1600	x4649
375A	Divisible by Seven math, number theory	1600	x4649
353C	Find Maximum implementation, math, number theory	1600	x4712
1493D	GCD of an Array brute force, data structures, hashing, implementation, math, number theory, sortings, two pointers	2100	x4733
337C	Quiz binary search, greedy, math, matrices, number theory	1600	x4765
1593D2	Half of Same brute force, math, number theory	1900	x4787
68A	Irrational problem implementation, number theory	1100	x4799
1485D	Multiples and Power Differences constructive algorithms, graphs, math, number theory	2200	x4929
1371E1	Asterism (Easy Version) binary search, brute force, combinatorics, math, number theory, sortings	1900	x4947
923A	Primal Sport math, number theory	1700	x4965
568A	Primes or Palindromes? brute force, implementation, math, number theory	1600	x4998
630K	Indivisibility math, number theory	1500	x5016
1513D	GCD and MST constructive algorithms, dsu, graphs, greedy, number theory, sortings	2000	x5021
914D	Bash and a Tough Math Puzzle data structures, number theory	1900	x5032
1647D	Madoka and the Best School in Russia constructive algorithms, dp, math, number theory	1900	x5097
1367E	Necklace Assembly brute force, dfs and similar, dp, graphs, greedy, number theory	1900	x5124
1176D	Recover it! dfs and similar, graphs, greedy, number theory, sortings	1800	x5125
248B	Chilly Willy math, number theory	1400	x5187
1781D	Many Perfect Squares brute force, math, number theory	1800	x5222
1749D	Counting Arrays combinatorics, dp, math, number theory	1900	x5242
1744E2	Divisible Numbers (hard version) brute force, math, number theory	1900	x5243
621C	Wet Shark and Flowers combinatorics, math, number theory, probabilities	1700	x5279
1561D1	Up the Strip (simplified version) brute force, data structures, dp, math, number theory	1700	x5380
552C	Vanya and Scales brute force, dp, greedy, math, meet-in-the-middle, number theory	1900	x5381
1713D	Tournament Countdown constructive algorithms, greedy, interactive, number theory, probabilities	1800	x5431
1499D	The Number of Pairs dp, math, number theory	2100	x5442
1547F	Array Stabilization (GCD version) binary search, brute force, data structures, divide and conquer, number theory, two pointers	1900	x5483
687B	Remainders Game chinese remainder theorem, math, number theory	1800	x5535
1750D	Count GCD combinatorics, math, number theory	1800	x5536
237C	Primes on Interval binary search, number theory, two pointers	1600	x5542
798C	Mike and gcd problem dp, greedy, number theory	1700	x5575
1477A	Nezzar and Board constructive algorithms, math, number theory	1800	x5658
1030D	Vasya and Triangle geometry, number theory	1800	x5672
1359E	Modular Stability combinatorics, math, number theory	2000	x5721