Problemset - Codeforces

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Codeforces Round (Div. 1 + Div. 2)
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number theory

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Problems

#	Name
803F	Coprime Subsequences bitmasks, combinatorics, number theory	2000	x3020
798C	Mike and gcd problem dp, greedy, number theory	1700	x5637
797A	k-Factorization implementation, math, number theory	1100	x14151
792E	Colored Balls greedy, math, number theory	2500	x1043
792C	Divide by Three dp, greedy, math, number theory	2000	x4227
787A	The Monster brute force, math, number theory	1200	x11062
785D	Anton and School - 2 combinatorics, dp, math, number theory	2300	x2652
776E	The Holmes Children math, number theory	2100	x2103
776B	Sherlock and his girlfriend constructive algorithms, number theory	1200	x19463
774G	Perfectionist Arkadiy *special problem, number theory	2700	x173
774F	Pens And Days Of Week *special problem, binary search, number theory	2700	x104
774E	Big Number and Remainder *special problem, math, number theory	2300	x206
773F	Test Data Generation combinatorics, divide and conquer, dp, fft, math, number theory	3400	x184
772C	Vulnerable Kerbals constructive algorithms, dp, graphs, math, number theory	2300	x1189
768F	Barrels and boxes brute force, combinatorics, math, number theory, probabilities	2300	x998
766B	Mahmoud and a Triangle constructive algorithms, geometry, greedy, math, number theory, sortings	1000	x31272
765G	Math, math everywhere brute force, dp, math, meet-in-the-middle, number theory	3200	x81
763C	Timofey and remoduling brute force, implementation, math, number theory	2600	x704
762A	k-th divisor math, number theory	1400	x18181
758F	Geometrical Progression brute force, math, number theory	2400	x620
758B	Blown Garland brute force, implementation, number theory	1100	x10071
757E	Bash Plays with Functions brute force, combinatorics, dp, number theory	2500	x1268
757B	Bash's Big Day greedy, math, number theory	1400	x9900
756F	Long number expression parsing, math, number theory	3400	x89
755G	PolandBall and Many Other Balls combinatorics, divide and conquer, dp, fft, math, number theory	3200	x864
755A	PolandBall and Hypothesis brute force, graphs, math, number theory	800	x17563
749A	Bachgold Problem greedy, implementation, math, number theory	800	x46785
743C	Vladik and fractions brute force, constructive algorithms, math, number theory	1500	x11867
742B	Arpa’s obvious problem and Mehrdad’s terrible solution brute force, math, number theory	1500	x9061
742A	Arpa’s hard exam and Mehrdad’s naive cheat implementation, math, number theory	1000	x40119
735D	Taxes math, number theory	1600	x12789
735B	Urbanization greedy, number theory, sortings	1100	x8305
731F	Video Cards brute force, data structures, implementation, math, number theory	1900	x2762
724G	Xor-matic Number of the Graph bitmasks, graphs, math, number theory, trees	2600	x1001
724C	Ray Tracing greedy, hashing, implementation, math, number theory, sortings	1800	x2113
722F	Cyclic Cipher chinese remainder theorem, data structures, implementation, number theory, two pointers	2800	x470
717A	Festival Organization combinatorics, math, number theory	2900	x333
711E	ZS and The Birthday Paradox math, number theory, probabilities	2300	x1244
710D	Two Arithmetic Progressions math, number theory	2500	x1165
707C	Pythagorean Triples math, number theory	1500	x12314
703E	Mishka and Divisors dp, number theory	2600	x587
698F	Coprime Permutation combinatorics, number theory	3000	x431
691F	Couple Cover brute force, dp, number theory	2200	x1248
687B	Remainders Game chinese remainder theorem, math, number theory	1800	x5574
682A	Alyona and Numbers constructive algorithms, math, number theory	1100	x20620
678D	Iterated Linear Function math, number theory	1700	x4288
678C	Joty and Chocolate implementation, math, number theory	1600	x9093
671C	Ultimate Weirdness of an Array data structures, number theory	2800	x663
665F	Four Divisors data structures, dp, math, number theory, sortings, two pointers	2400	x577
665D	Simple Subset constructive algorithms, greedy, number theory	1800	x3213
664A	Complicated GCD math, number theory	800	x17486
660A	Co-prime Array greedy, implementation, math, number theory	1200	x8554
659G	Fence Divercity combinatorics, dp, number theory	2300	x947
653G	Move by Prime combinatorics, math, number theory	3100	x516
645F	Cowslip Collections combinatorics, math, number theory	2500	x759
633G	Yash And Trees bitmasks, data structures, dfs and similar, math, number theory	2800	x722
633B	A Trivial Problem brute force, constructive algorithms, math, number theory	1300	x6547
633A	Ebony and Ivory brute force, math, number theory	1100	x12371
632D	Longest Subsequence brute force, math, number theory	2100	x3399
630K	Indivisibility math, number theory	1500	x5050
630J	Divisibility math, number theory	1100	x10708
630A	Again Twenty Five! number theory	800	x62422
626C	Block Towers brute force, greedy, math, number theory	1600	x4288
623B	Array GCD dp, greedy, number theory	2300	x2046
621C	Wet Shark and Flowers combinatorics, math, number theory, probabilities	1700	x5302
616E	Sum of Remainders implementation, math, number theory	2200	x2711
615D	Multipliers math, number theory	2000	x3811
603B	Moodular Arithmetic combinatorics, dfs and similar, dsu, math, number theory	1800	x2538
594D	REQ data structures, number theory	2500	x1517
585E	Present for Vitalik the Philatelist combinatorics, math, number theory	2900	x1044
585C	Alice, Bob, Oranges and Apples number theory	2400	x962
584D	Dima and Lisa brute force, math, number theory	1800	x8864
582D	Number of Binominal Coefficients dp, math, number theory	3300	x608
582C	Superior Periodic Subarrays number theory	2400	x726
582A	GCD Table constructive algorithms, greedy, number theory	1700	x7553
577A	Multiplication Table implementation, number theory	1000	x38248
576A	Vasya and Petya's Game math, number theory	1500	x13374
575H	Bots combinatorics, dp, math, number theory	1800	x1634
573A	Bear and Poker implementation, math, number theory	1300	x16316
568A	Primes or Palindromes? brute force, implementation, math, number theory	1600	x5002
566F	Clique in the Divisibility Graph dp, math, number theory	1500	x3529
559C	Gerald and Giant Chess combinatorics, dp, math, number theory	2200	x6165
552C	Vanya and Scales brute force, dp, greedy, math, meet-in-the-middle, number theory	1900	x5391
551D	GukiZ and Binary Operations combinatorics, implementation, math, matrices, number theory	2100	x1724
547C	Mike and Foam bitmasks, combinatorics, dp, math, number theory	2300	x2711
546D	Soldier and Number Game constructive algorithms, dp, math, number theory	1700	x11286
542D	Superhero's Job dfs and similar, dp, hashing, math, number theory	2600	x497
520E	Pluses everywhere combinatorics, dp, math, number theory	2200	x1810
519C	A and B and Team Training greedy, implementation, math, number theory	1300	x19352
516E	Drazil and His Happy Friends math, number theory	3100	x474
515B	Drazil and His Happy Friends brute force, dsu, meet-in-the-middle, number theory	1300	x7369
500G	New Year Running number theory, trees	3200	x156
498D	Traffic Jams in the Land data structures, dp, number theory	2400	x1064
498C	Array and Operations flows, graph matchings, number theory	2100	x3311
495B	Modular Equations math, number theory	1600	x6526
490D	Chocolate brute force, dfs and similar, math, meet-in-the-middle, number theory	1900	x2070
490C	Hacking Cypher brute force, math, number theory, strings	1700	x8915
487C	Prefix Product Sequence constructive algorithms, math, number theory	2300	x2516
483A	Counterexample brute force, implementation, math, number theory	1100	x22280
474F	Ant colony data structures, math, number theory	2100	x7766