Problemset - Codeforces

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Ethflow Round 1 (Codeforces Round, Div. 1 + Div. 2)
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Problems

#	Name
1367E	Necklace Assembly brute force, dfs and similar, dp, graphs, greedy, number theory	1900	x5538
1367D	Task On The Board constructive algorithms, greedy, implementation, sortings	1800	x8430
1367C	Social Distance constructive algorithms, greedy, math	1300	x23843
1367B	Even Array greedy, math	800	x55481
1367A	Short Substrings implementation, strings	800	x59018
1366G	Construct the String data structures, dp, strings	2700	x569
1366F	Jog Around The Graph binary search, dp, geometry, graphs	2700	x833
1366E	Two Arrays binary search, brute force, combinatorics, constructive algorithms, dp, two pointers	2100	x4330
1366D	Two Divisors constructive algorithms, math, number theory	2000	x10840
1366C	Palindromic Paths greedy, math	1500	x13672
1366B	Shuffle math, two pointers	1300	x21802
1366A	Shovels and Swords binary search, greedy, math	1100	x30750
1365G	Secure Password bitmasks, combinatorics, constructive algorithms, interactive, math	2800	x1189
1365F	Swaps Again constructive algorithms, implementation, sortings	2100	x4505
1365E	Maximum Subsequence Value brute force, constructive algorithms	1900	x7947
1365D	Solve The Maze constructive algorithms, dfs and similar, dsu, graphs, greedy, implementation, shortest paths	1700	x17931
1365C	Rotation Matching constructive algorithms, data structures, greedy, implementation	1400	x23482
1365B	Trouble Sort constructive algorithms, implementation	1300	x27277
1365A	Matrix Game games, greedy, implementation	1100	x24306
1364E	X-OR bitmasks, constructive algorithms, divide and conquer, interactive, probabilities	2700	x1452
1364D	Ehab's Last Corollary constructive algorithms, dfs and similar, graphs, greedy, implementation, trees	2100	x4486
1364C	Ehab and Prefix MEXs brute force, constructive algorithms, greedy	1600	x13374
1364B	Most socially-distanced subsequence greedy, two pointers	1300	x20570
1364A	XXXXX brute force, data structures, number theory, two pointers	1200	x28792
1363F	Rotating Substrings dp, strings	2600	x1591
1363E	Tree Shuffling dfs and similar, dp, greedy, trees	2000	x6913
1363D	Guess The Maximums binary search, implementation, interactive, math	2100	x4122
1363C	Game On Leaves games, trees	1600	x19175
1363B	Subsequence Hate implementation, strings	1400	x24047
1363A	Odd Selection brute force, implementation, math	1200	x36734
1362C	Johnny and Another Rating Drop bitmasks, greedy, math	1400	x19069
1362B	Johnny and His Hobbies bitmasks, brute force	1200	x19669
1362A	Johnny and Ancient Computer implementation	1000	x25186
1361F	Johnny and New Toy data structures, implementation, math	3300	x157
1361E	James and the Chase dfs and similar, graphs, probabilities, trees	3000	x717
1361D	Johnny and James greedy, implementation, math, trees	2900	x323
1361C	Johnny and Megan's Necklace binary search, bitmasks, constructive algorithms, dfs and similar, dsu, graphs	2500	x1671
1361B	Johnny and Grandmaster greedy, implementation, math, sortings	1900	x3715
1361A	Johnny and Contribution constructive algorithms, graphs, greedy, sortings	1700	x8489
1360H	Binary Median binary search, bitmasks, brute force, constructive algorithms	2100	x4643
1360G	A/B Matrix constructive algorithms, greedy, math	1900	x7896
1360F	Spy-string bitmasks, brute force, constructive algorithms, dp, hashing, strings	1700	x12626
1360E	Polygon dp, graphs, implementation, shortest paths	1300	x25888
1360D	Buying Shovels math, number theory	1300	x34522
1360C	Similar Pairs constructive algorithms, graph matchings, greedy, sortings	1100	x33428
1360B	Honest Coach greedy, sortings	800	x48991
1360A	Minimal Square greedy, math	800	x52269
1359F	RC Kaboom Show binary search, brute force, data structures, geometry, math	2900	x546
1359E	Modular Stability combinatorics, math, number theory	2000	x6204
1359D	Yet Another Yet Another Task data structures, dp, implementation, two pointers	2000	x9688
1359C	Mixing Water binary search, math	1700	x14077
1359B	New Theatre Square brute force, dp, greedy, implementation, two pointers	1000	x28106
1359A	Berland Poker brute force, greedy, math	1000	x30024
1358F	Tasty Cookie binary search, constructive algorithms, greedy, implementation	2700	x466
1358E	Are You Fired? constructive algorithms, data structures, greedy, implementation	2400	x2353
1358D	The Best Vacation binary search, brute force, greedy, implementation, two pointers	1900	x8295
1358C	Celex Update math	1600	x17602
1358B	Maria Breaks the Self-isolation greedy, sortings	1000	x25109
1358A	Park Lighting greedy, math	800	x40187
1357E2	Root of quantum Fourier transform *special problem		x51
1357E1	Power of quantum Fourier transform *special problem		x193
1357D5	Quantum Classification - Dataset 7 *special problem		x82
1357D4	Quantum Classification - Dataset 6 *special problem		x85
1357D3	Quantum Classification - Dataset 5 *special problem		x105
1357D2	Quantum Classification - Dataset 4 *special problem		x112
1357D1	Quantum Classification - Dataset 3 *special problem		x125
1357C2	Prepare superposition of basis states with the same parity *special problem		x304
1357C1	Prepare superposition of basis states with 0s *special problem		x348
1357B2	"Is the number divisible by 3?" oracle *special problem		x214
1357B1	"Is the bit string balanced?" oracle *special problem		x214
1357A7	Distinguish Y, XZ, -Y and -XZ *special problem		x183
1357A6	Distinguish four Pauli gates *special problem		x168
1357A5	Distinguish Rz(θ) from Ry(θ) *special problem		x241
1357A4	Distinguish Rz from R1 *special problem		x352
1357A3	Distinguish H from X *special problem		x479
1357A2	Distinguish I, CNOTs and SWAP *special problem		x511
1357A1	Figure out direction of CNOT *special problem		x632
1356D2	Quantum Classification - 2 *special problem		x128
1356D1	Quantum Classification - 1 *special problem		x137
1356C	Prepare state \|01⟩ + \|10⟩ + \|11⟩ *special problem		x303
1356B2	Decrement *special problem		x283
1356B1	Increment *special problem		x283
1356A5	Distinguish Z from -Z *special problem		x331
1356A4	Distinguish I ⊗ X from CNOT *special problem		x459
1356A3	Distinguish Z from S *special problem		x461
1356A2	Distinguish I from Z *special problem		x488
1356A1	Distinguish I from X *special problem		x603
1355F	Guess Divisors Count constructive algorithms, interactive, number theory	2600	x882
1355E	Restorer Distance binary search, greedy, math, sortings, ternary search	2100	x5263
1355D	Game With Array constructive algorithms, math	1400	x18237
1355C	Count Triangles binary search, implementation, math, two pointers	1800	x10835
1355B	Young Explorers dp, greedy, sortings	1200	x26043
1355A	Sequence with Digits brute force, implementation, math	1200	x27018
1354G	Find a Gift binary search, interactive, probabilities	2600	x808
1354F	Summoning Minions constructive algorithms, dp, flows, graph matchings, greedy, sortings	2500	x1247
1354E	Graph Coloring dfs and similar, dp, graphs	2100	x3425
1354D	Multiset binary search, data structures	1900	x9034
1354C2	Not So Simple Polygon Embedding binary search, brute force, geometry, math	2000	x6137
1354C1	Simple Polygon Embedding binary search, geometry, math, ternary search	1400	x15889
1354B	Ternary String binary search, dp, implementation, two pointers	1200	x31693