Problemset - Codeforces

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Codeforces Global Round 28
23:13:11
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Problems

#	Name
1770D	Koxia and Game constructive algorithms, data structures, dfs and similar, dsu, flows, games, graph matchings, graphs, implementation	2000	x3915
1767C	Count Binary Strings data structures, dp	2100	x2696
1764D	Doremy's Pegging Game combinatorics, dp, math	2000	x2822
1763C	Another Array Problem brute force, constructive algorithms, greedy	2000	x6817
1762D	GCD Queries constructive algorithms, interactive, number theory	2100	x3719
1761D	Carry Bit combinatorics, math	2100	x2495
1759G	Restore the Permutation binary search, constructive algorithms, data structures, greedy, math	1900	x4565
1753C	Wish I Knew How to Sort dp, math, probabilities	2000	x4597
1749D	Counting Arrays combinatorics, dp, math, number theory	1900	x5652
1748D	ConstructOR bitmasks, chinese remainder theorem, combinatorics, constructive algorithms, math, number theory	2100	x2868
1747D	Yet Another Problem binary search, bitmasks, constructive algorithms, data structures	1900	x4756
1746D	Paths on the Tree dfs and similar, dp, greedy, sortings, trees	1900	x4701
1744F	MEX vs MED math, two pointers	2000	x3167
1744E2	Divisible Numbers (hard version) brute force, math, number theory	1900	x5705
1741F	Multi-Colored Segments binary search, data structures, math, sortings	2000	x2497
1739D	Reset K Edges binary search, data structures, dfs and similar, graphs, greedy, trees	1900	x5262
1738D	Permutation Addicts constructive algorithms, data structures, dfs and similar, dsu, graphs, trees	1900	x3484
1734E	Rectangular Congruence constructive algorithms, number theory	2100	x2962
1733D2	Zero-One (Hard Version) dp, greedy	2000	x4306
1732C2	Sheikh (Hard Version) binary search, bitmasks, brute force, greedy, implementation, two pointers	2100	x2637
1731E	Graph Cost dp, greedy, math, number theory	2000	x2906
1729G	Cut Substrings combinatorics, dp, hashing, strings, two pointers	2100	x2243
1729F	Kirei and the Linear Function hashing, math	1900	x4202
1726D	Edge Split brute force, constructive algorithms, dfs and similar, dsu, graphs, probabilities, trees	2000	x3767
1725F	Field Photography bitmasks, data structures, sortings	2100	x1005
1725C	Circular Mirror binary search, combinatorics, geometry, math, two pointers	2000	x1663
1718B	Fibonacci Strings greedy, implementation, math, number theory	2000	x3061
1718A2	Burenka and Traditions (hard version) data structures, dp, greedy	1900	x5353
1717D	Madoka and The Corruption Scheme combinatorics, constructive algorithms, greedy, math	1900	x4460
1716D	Chip Move brute force, dp, math	2000	x5356
1716C	Robot in a Hallway data structures, dp, greedy, implementation, ternary search	2000	x4252
1715D	2+ doors 2-sat, bitmasks, graphs, greedy	1900	x5233
1714F	Build a Tree and That Is It constructive algorithms, implementation, trees	1900	x3304
1712D	Empty Graph binary search, constructive algorithms, data structures, greedy, shortest paths	2000	x4588
1710B	Rain binary search, brute force, data structures, geometry, greedy, implementation, math	2100	x2506
1707B	Difference Array brute force, data structures, implementation, sortings	1900	x5834
1704D	Magical Array constructive algorithms, hashing, implementation, math	1900	x5087
1702G2	Passable Paths (hard version) data structures, dfs and similar, trees	2000	x4762
1702G1	Passable Paths (easy version) dfs and similar, trees	1900	x5539
1701D	Permutation Restoration binary search, data structures, greedy, math, sortings, two pointers	1900	x5742
1700D	River Locks binary search, dp, greedy, math	1900	x6194
1697D	Guess The String binary search, constructive algorithms, interactive	1900	x4516
1696E	Placing Jinas combinatorics, math	2000	x4157
1696D	Permutation Graph binary search, constructive algorithms, data structures, divide and conquer, greedy, shortest paths	1900	x5527
1690G	Count the Trains binary search, data structures, greedy, sortings	2000	x3461
1689D	Lena and Matrix data structures, dp, geometry, shortest paths	1900	x4268
1685B	Linguistics greedy, implementation, sortings, strings	2000	x3315
1684E	MEX vs DIFF binary search, brute force, constructive algorithms, data structures, greedy, two pointers	2100	x3213
1682D	Circular Spanning Tree constructive algorithms, implementation, trees	2000	x3359
1680E	Moving Chips bitmasks, dp, greedy	2000	x3845
1679D	Toss a Coin to Your Graph... binary search, dfs and similar, dp, graphs	1900	x4974
1677C	Tokitsukaze and Two Colorful Tapes constructive algorithms, dfs and similar, graphs, greedy	1900	x3658
1674G	Remove Directed Edges dfs and similar, dp, graphs	2000	x2557
1674E	Breaking the Wall binary search, brute force, constructive algorithms, greedy, math	2000	x6536
1673D	Lost Arithmetic Progression combinatorics, math, number theory	1900	x3346
1672F1	Array Shuffling constructive algorithms, graphs, greedy	2000	x3154
1671E	Preorder combinatorics, divide and conquer, dp, dsu, hashing, sortings, trees	2100	x2782
1667B	Optimal Partition data structures, dp	2100	x3788
1666J	Job Lookup constructive algorithms, dp, shortest paths, trees	2100	x1387
1665D	GCD Guess bitmasks, chinese remainder theorem, constructive algorithms, games, interactive, math, number theory	2000	x4056
1661D	Progressions Covering data structures, greedy	1900	x4809
1660F2	Promising String (hard version) data structures, implementation, math, strings	2100	x2777
1659D	Reverse Sort Sum constructive algorithms, data structures, greedy, implementation, math, two pointers	1900	x4067
1657D	For Gamers. By Gamers. binary search, brute force, greedy, math, sortings	2000	x4952
1656D	K-good constructive algorithms, math, number theory	1900	x6947
1654D	Potion Brewing Class dfs and similar, math, number theory, trees	2100	x2875
1651D	Nearest Excluded Points binary search, data structures, dfs and similar, graphs, shortest paths	1900	x5245
1650G	Counting Shortcuts data structures, dfs and similar, dp, graphs, shortest paths	2100	x2533
1650E	Rescheduling the Exam binary search, data structures, greedy, implementation, math, sortings	1900	x4190
1648C	Tyler and Strings combinatorics, data structures, implementation	1900	x3011
1647D	Madoka and the Best School in Russia constructive algorithms, dp, math, number theory	1900	x5344
1646D	Weight the Tree constructive algorithms, dfs and similar, dp, implementation, trees	2000	x3845
1644E	Expand the Path brute force, combinatorics, data structures, implementation, math	1900	x3139
1641B	Repetitions Decoding constructive algorithms, implementation, sortings	2000	x3841
1638D	Big Brush constructive algorithms, data structures, greedy, implementation	2000	x4259
1637E	Best Pair binary search, brute force, implementation	2100	x3409
1634D	Finding Zero constructive algorithms, interactive, math	2000	x4427
1632D	New Year Concert binary search, data structures, greedy, math, number theory, two pointers	2000	x4770
1628D1	Game on Sum (Easy Version) combinatorics, dp, games, math	2100	x3241
1627D	Not Adding brute force, dp, math, number theory	1900	x8425
1626D	Martial Arts Tournament binary search, brute force, greedy, math	2100	x3949
1624G	MinOr Tree bitmasks, dfs and similar, dsu, graphs, greedy	1900	x6148
1624F	Interacdive Problem binary search, constructive algorithms, interactive	2000	x3408
1624E	Masha-forgetful brute force, constructive algorithms, dp, hashing, implementation, strings	2000	x4162
1622D	Shuffle combinatorics, math, two pointers	2000	x4155
1621D	The Winter Hike constructive algorithms, greedy, math	2100	x4101
1620E	Replace the Numbers constructive algorithms, data structures, dsu, implementation	1900	x8438
1620D	Exact Change brute force, constructive algorithms, greedy	2000	x4262
1619G	Unusual Minesweeper binary search, dfs and similar, dsu, greedy, sortings	2000	x2438
1619F	Let's Play the Hat? brute force, constructive algorithms, greedy, math	2000	x2131
1618F	Reverse bitmasks, constructive algorithms, dfs and similar, implementation, math, strings	2000	x4304
1616D	Keep the Average High dp, greedy, math	2000	x4963
1614D1	Divan and Kostomuksha (easy version) dp, number theory	2100	x3995
1613E	Crazy Robot dfs and similar, graphs	2000	x5244
1613D	MEX Sequences dp, math	1900	x4764
1612E	Messages brute force, dp, greedy, probabilities, sortings	2000	x2569
1611E2	Escape The Maze (hard version) dfs and similar, dp, greedy, shortest paths, trees	1900	x3881
1610D	Not Quite Lee combinatorics, dp, math, number theory	2000	x2753
1606E	Arena combinatorics, dp, math	2100	x3601
1605D	Treelabeling bitmasks, constructive algorithms, dfs and similar, games, greedy, implementation, trees	2100	x2971