Problemset - Codeforces

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Codeforces Round (Div. 2)
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number theory

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Problems

#	Name
1419E	Decryption constructive algorithms, implementation, math, number theory	2100	x3163
1418F	Equal Product data structures, math, number theory, two pointers	3000	x358
1411B	Fair Numbers brute force, number theory	1000	x18340
1409C	Yet Another Array Restoration brute force, math, number theory	1200	x22937
1407B	Big Vova brute force, greedy, math, number theory	1300	x16768
1406E	Deleting Numbers interactive, math, number theory	2600	x1579
1404D	Game of Pairs constructive algorithms, dfs and similar, interactive, math, number theory	2800	x995
1401D	Maximum Distributed Tree dfs and similar, dp, greedy, implementation, math, number theory, sortings, trees	1800	x8938
1401C	Mere Array constructive algorithms, math, number theory, sortings	1300	x23703
1398G	Running Competition bitmasks, fft, math, number theory	2600	x845
1397B	Power Sequence brute force, math, number theory, sortings	1500	x14447
1396A	Multiples of Length constructive algorithms, greedy, number theory	1600	x15108
1389E	Calendar Ambiguity math, number theory	2200	x3196
1389A	LCM Problem constructive algorithms, greedy, math, number theory	800	x39526
1388A	Captain Flint and Crew Recruitment brute force, greedy, math, number theory	800	x24662
1379B	Dubious Cyrpto binary search, brute force, math, number theory	1500	x12546
1375I	Cubic Lattice geometry, math, matrices, number theory	3500	x127
1372B	Omkar and Last Class of Math greedy, math, number theory	1300	x26799
1371E2	Asterism (Hard Version) binary search, combinatorics, dp, math, number theory, sortings	2300	x2313
1371E1	Asterism (Easy Version) binary search, brute force, combinatorics, math, number theory, sortings	1900	x5038
1370C	Number Game games, math, number theory	1400	x23899
1370B	GCD Compression constructive algorithms, math, number theory	1100	x23293
1370A	Maximum GCD greedy, implementation, math, number theory	800	x50150
1367E	Necklace Assembly brute force, dfs and similar, dp, graphs, greedy, number theory	1900	x5236
1366D	Two Divisors constructive algorithms, math, number theory	2000	x10114
1364A	XXXXX brute force, data structures, number theory, two pointers	1200	x27264
1360D	Buying Shovels math, number theory	1300	x31674
1359E	Modular Stability combinatorics, math, number theory	2000	x5854
1355F	Guess Divisors Count constructive algorithms, interactive, number theory	2600	x824
1350B	Orac and Models dp, math, number theory	1400	x21177
1349A	Orac and LCM data structures, math, number theory	1600	x16419
1346G	Two IP Cameras *special problem, math, number theory	2300	x133
1344A	Hilbert's Hotel math, number theory, sortings	1600	x15502
1342C	Yet Another Counting Problem math, number theory	1600	x13892
1334E	Divisor Paths combinatorics, graphs, greedy, math, number theory	2200	x2791
1333F	Kate and imperfection greedy, implementation, math, number theory, sortings, two pointers	2200	x4193
1332B	Composite Coloring brute force, constructive algorithms, greedy, math, number theory	1400	x17402
1331B	Limericks *special problem, math, number theory		x6988
1327D	Infinite Path brute force, dfs and similar, graphs, math, number theory	2200	x3240
1326A	Bad Ugly Numbers constructive algorithms, number theory	1000	x29891
1325E	Ehab's REAL Number Theory Problem brute force, dfs and similar, graphs, number theory, shortest paths	2600	x2003
1325D	Ehab the Xorcist bitmasks, constructive algorithms, greedy, number theory	1700	x11841
1325A	EhAb AnD gCd constructive algorithms, greedy, number theory	800	x38979
1324A	Yet Another Tetris Problem implementation, number theory	900	x25693
1322C	Instant Noodles graphs, hashing, math, number theory	2300	x2364
1312C	Adding Powers bitmasks, greedy, implementation, math, number theory, ternary search	1400	x16204
1312A	Two Regular Polygons geometry, greedy, math, number theory	800	x25624
1310F	Bad Cryptography math, number theory	3400	x71
1305F	Kuroni and the Punishment math, number theory, probabilities	2500	x2542
1305C	Kuroni and Impossible Calculation brute force, combinatorics, math, number theory	1600	x14124
1295D	Same GCDs math, number theory	1800	x8642
1294C	Product of Three Numbers greedy, math, number theory	1300	x33366
1292D	Chaotic V. dp, graphs, greedy, math, number theory, trees	2700	x785
1285F	Classical? binary search, combinatorics, number theory	2900	x1088
1285C	Fadi and LCM brute force, math, number theory	1400	x22718
1278F	Cards combinatorics, dp, math, number theory, probabilities	2600	x1781
1277B	Make Them Odd greedy, number theory	1200	x14938
1266C	Diverse Matrix constructive algorithms, greedy, math, number theory	1400	x9546
1264F	Beautiful Fibonacci Problem constructive algorithms, number theory	3500	x885
1263C	Everyone is a Winner! binary search, math, meet-in-the-middle, number theory	1400	x13545
1260C	Infinite Fence greedy, math, number theory	1700	x8141
1257G	Divisor Set divide and conquer, fft, greedy, math, number theory	2600	x584
1254B2	Send Boxes to Alice (Hard Version) constructive algorithms, greedy, math, number theory, ternary search, two pointers	2100	x3104
1254B1	Send Boxes to Alice (Easy Version) constructive algorithms, greedy, math, number theory, ternary search, two pointers	1800	x4570
1245A	Good ol' Numbers Coloring math, number theory	1000	x14078
1244C	The Football Season brute force, math, number theory	2000	x7469
1242A	Tile Painting constructive algorithms, math, number theory	1500	x12484
1238A	Prime Subtraction math, number theory	900	x23694
1228C	Primes and Multiplication math, number theory	1700	x8907
1225G	To Make 1 bitmasks, constructive algorithms, dp, greedy, number theory	3100	x527
1225D	Power Products hashing, math, number theory	1800	x7678
1223G	Wooden Raft binary search, math, number theory	3200	x228
1220D	Alex and Julian bitmasks, math, number theory	1900	x3857
1220B	Multiplication Table math, number theory	1300	x11524
1210C	Kamil and Making a Stream math, number theory, trees	2000	x3229
1209B	Koala and Lights implementation, math, number theory	1300	x8115
1208G	Polygons greedy, math, number theory	2800	x737
1204E	Natasha, Sasha and the Prefix Sums combinatorics, dp, math, number theory	2300	x1609
1200F	Graph Traveler brute force, data structures, dfs and similar, dp, graphs, implementation, math, number theory	2300	x1056
1200C	Round Corridor math, number theory	1400	x9759
1198F	GCD Groups 2 greedy, number theory, probabilities	2900	x840
1195D2	Submarine in the Rybinsk Sea (hard edition) combinatorics, math, number theory	1800	x4567
1195D1	Submarine in the Rybinsk Sea (easy edition) combinatorics, math, number theory	1500	x7805
1194F	Crossword Expert combinatorics, dp, number theory, probabilities, two pointers	2400	x979
1190F	Tokitsukaze and Powers number theory, probabilities	3400	x92
1188B	Count Pairs math, matrices, number theory, two pointers	2300	x4398
1184A3	Heidi Learns Hashing (Hard) fft, math, number theory	3100	x139
1184A2	Heidi Learns Hashing (Medium) brute force, number theory	2100	x946
1184A1	Heidi Learns Hashing (Easy) brute force, math, number theory	1200	x5892
1182F	Maximum Sine binary search, data structures, number theory	2700	x333
1182E	Product Oriented Recurrence dp, math, matrices, number theory	2300	x2596
1178D	Prime Graph constructive algorithms, greedy, math, number theory	1500	x7305
1176D	Recover it! dfs and similar, graphs, greedy, number theory, sortings	1800	x5194
1174E	Ehab and the Expected GCD Problem combinatorics, dp, math, number theory	2500	x1377
1174C	Ehab and a Special Coloring Problem constructive algorithms, number theory	1300	x11883
1166E	The LCMs Must be Large bitmasks, brute force, constructive algorithms, math, number theory	2100	x2798
1166B	All the Vowels Please constructive algorithms, math, number theory	1100	x11375
1165D	Almost All Divisors math, number theory	1600	x15574
1155C	Alarm Clocks Everywhere math, number theory	1300	x9103
1154G	Minimum Possible LCM brute force, greedy, math, number theory	2200	x2661