Problemset - Codeforces

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Codeforces Round (Div. 2)
4 days
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Difficulty: —

number theory

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Problems

#	Name
919B	Perfect Number binary search, brute force, dp, implementation, number theory	1100	x28049
915G	Coprime Arrays math, number theory	2300	x1231
914D	Bash and a Tough Math Puzzle data structures, number theory	1900	x5284
913G	Power Substring math, number theory	3200	x208
912E	Prime Gift binary search, dfs and similar, math, meet-in-the-middle, number theory, two pointers	2400	x1579
912B	New Year's Eve bitmasks, constructive algorithms, number theory	1300	x12016
906D	Power Tower chinese remainder theorem, math, number theory	2700	x2103
900D	Unusual Sequences bitmasks, combinatorics, dp, math, number theory	2000	x3220
900B	Position in Fraction math, number theory	1300	x7824
898B	Proper Nutrition brute force, implementation, number theory	1100	x9564
896D	Nephren Runs a Cinema chinese remainder theorem, combinatorics, math, number theory	2900	x529
894B	Ralph And His Magic Field combinatorics, constructive algorithms, math, number theory	1800	x4464
893E	Counting Arrays combinatorics, dp, math, number theory	2000	x3643
891A	Pride brute force, dp, greedy, math, number theory	1500	x10145
876B	Divisiblity of Differences implementation, math, number theory	1300	x9136
870F	Paths data structures, number theory	2700	x614
870C	Maximum splitting dp, greedy, math, number theory	1300	x9093
858A	k-rounding brute force, math, number theory	1100	x8007
852F	Product transformation combinatorics, math, number theory	2200	x570
850B	Arpa and a list of numbers implementation, number theory	2100	x2023
842C	Ilya And The Tree dfs and similar, graphs, math, number theory, trees	2000	x3479
840A	Leha and Function combinatorics, greedy, math, number theory, sortings	1300	x6996
839D	Winter is here combinatorics, dp, math, number theory	2200	x2910
838D	Airplane Arrangements math, number theory	2700	x904
833A	The Meaningless Game math, number theory	1700	x6178
830C	Bamboo Partition brute force, data structures, implementation, math, number theory, sortings, two pointers	2300	x1200
822D	My pretty girl Noora brute force, dp, greedy, math, number theory	1800	x3086
822A	I'm bored with life implementation, math, number theory	800	x32985
819D	Mister B and Astronomers number theory	2900	x263
819C	Mister B and Beacons on Field number theory	2900	x211
818E	Card Game Again binary search, data structures, number theory, two pointers	1900	x2268
817A	Treasure Hunt implementation, math, number theory	1200	x6232
809E	Surprise me! divide and conquer, math, number theory, trees	3100	x733
804F	Fake bullions combinatorics, dfs and similar, dp, graphs, number theory	3400	x164
803F	Coprime Subsequences bitmasks, combinatorics, number theory	2000	x3237
798C	Mike and gcd problem dp, greedy, number theory	1700	x5799
797A	k-Factorization implementation, math, number theory	1100	x15282
792E	Colored Balls greedy, math, number theory	2500	x1082
792C	Divide by Three dp, greedy, math, number theory	2000	x4387
787A	The Monster brute force, math, number theory	1200	x11349
785D	Anton and School - 2 combinatorics, dp, math, number theory	2300	x2958
776E	The Holmes Children math, number theory	2100	x2173
776B	Sherlock and his girlfriend constructive algorithms, number theory	1200	x20762
774G	Perfectionist Arkadiy *special problem, number theory	2700	x180
774F	Pens And Days Of Week *special problem, binary search, number theory	2700	x108
774E	Big Number and Remainder *special problem, math, number theory	2300	x215
773F	Test Data Generation combinatorics, divide and conquer, dp, fft, math, number theory	3400	x188
772C	Vulnerable Kerbals constructive algorithms, dp, graphs, math, number theory	2300	x1380
768F	Barrels and boxes brute force, combinatorics, math, number theory, probabilities	2300	x1021
766B	Mahmoud and a Triangle constructive algorithms, geometry, greedy, math, number theory, sortings	1000	x32763
765G	Math, math everywhere brute force, dp, math, meet-in-the-middle, number theory	3200	x85
763C	Timofey and remoduling brute force, implementation, math, number theory	2600	x712
762A	k-th divisor math, number theory	1400	x19666
758F	Geometrical Progression brute force, math, number theory	2400	x628
758B	Blown Garland brute force, implementation, number theory	1100	x10198
757E	Bash Plays with Functions brute force, combinatorics, dp, number theory	2500	x1326
757B	Bash's Big Day greedy, math, number theory	1400	x10220
756F	Long number expression parsing, math, number theory	3400	x93
755G	PolandBall and Many Other Balls combinatorics, divide and conquer, dp, fft, math, number theory	3200	x911
755A	PolandBall and Hypothesis brute force, graphs, math, number theory	800	x18006
749A	Bachgold Problem greedy, implementation, math, number theory	800	x49054
743C	Vladik and fractions brute force, constructive algorithms, math, number theory	1500	x12263
742B	Arpa’s obvious problem and Mehrdad’s terrible solution brute force, math, number theory	1500	x9250
742A	Arpa’s hard exam and Mehrdad’s naive cheat implementation, math, number theory	1000	x42312
735D	Taxes math, number theory	1600	x13406
735B	Urbanization greedy, number theory, sortings	1100	x8385
731F	Video Cards brute force, data structures, implementation, math, number theory	1900	x2865
724G	Xor-matic Number of the Graph bitmasks, graphs, math, number theory, trees	2600	x1051
724C	Ray Tracing greedy, hashing, implementation, math, number theory, sortings	1800	x2139
722F	Cyclic Cipher chinese remainder theorem, data structures, implementation, number theory, two pointers	2800	x495
717A	Festival Organization combinatorics, math, number theory	2900	x352
711E	ZS and The Birthday Paradox math, number theory, probabilities	2300	x1270
710D	Two Arithmetic Progressions math, number theory	2500	x1301
707C	Pythagorean Triples math, number theory	1500	x12616
703E	Mishka and Divisors dp, number theory	2600	x594
698F	Coprime Permutation combinatorics, number theory	3000	x436
691F	Couple Cover brute force, dp, number theory	2200	x1298
687B	Remainders Game chinese remainder theorem, math, number theory	1800	x5842
682A	Alyona and Numbers constructive algorithms, math, number theory	1100	x21636
678D	Iterated Linear Function math, number theory	1700	x4500
678C	Joty and Chocolate implementation, math, number theory	1600	x9398
671C	Ultimate Weirdness of an Array data structures, number theory	2800	x685
665F	Four Divisors data structures, dp, math, number theory, sortings, two pointers	2400	x613
665D	Simple Subset constructive algorithms, greedy, number theory	1800	x3479
664A	Complicated GCD math, number theory	800	x18133
660A	Co-prime Array greedy, implementation, math, number theory	1200	x8886
659G	Fence Divercity combinatorics, dp, number theory	2300	x1183
653G	Move by Prime combinatorics, math, number theory	3100	x547
645F	Cowslip Collections combinatorics, math, number theory	2500	x787
633G	Yash And Trees bitmasks, data structures, dfs and similar, math, number theory	2800	x776
633B	A Trivial Problem brute force, constructive algorithms, math, number theory	1300	x6664
633A	Ebony and Ivory brute force, math, number theory	1100	x12697
632D	Longest Subsequence brute force, math, number theory	2100	x3756
630K	Indivisibility math, number theory	1500	x5252
630J	Divisibility math, number theory	1100	x11059
630A	Again Twenty Five! number theory	800	x67171
626C	Block Towers brute force, greedy, math, number theory	1600	x4335
623B	Array GCD dp, greedy, number theory	2300	x2153
621C	Wet Shark and Flowers combinatorics, math, number theory, probabilities	1700	x5455
616E	Sum of Remainders implementation, math, number theory	2200	x2898