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Codeforces Round 991 (Div. 3)
19:42:35
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combine-tags-by-or
*combine tags by OR
2-sat
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bitmasks
brute force
chinese remainder theorem
combinatorics
constructive algorithms
data structures
dfs and similar
divide and conquer
dp
dsu
expression parsing
fft
flows
games
geometry
graph matchings
graphs
greedy
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Problems
#
Name
2045M
Mirror Maze
brute force
,
dfs and similar
,
graphs
,
implementation
1800
x636
2039C2
Shohag Loves XOR (Hard Version)
bitmasks
,
brute force
,
math
,
number theory
1800
x3430
2035D
Yet Another Real Number Problem
binary search
,
data structures
,
divide and conquer
,
greedy
,
implementation
,
math
1800
x4539
2033F
Kosuke's Sloth
brute force
,
math
,
number theory
1800
x5324
2032D
Genokraken
constructive algorithms
,
data structures
,
graphs
,
greedy
,
implementation
,
interactive
,
trees
,
two pointers
1800
x4656
2025D
Attribute Checks
brute force
,
data structures
,
dp
,
implementation
,
math
,
two pointers
1800
x5986
2022C
Gerrymandering
dp
,
implementation
1800
x3959
2020D
Connect the Dots
brute force
,
dp
,
dsu
,
graphs
,
math
,
trees
1800
x5713
2014E
Rendez-vous de Marian et Robin
dfs and similar
,
graphs
,
shortest paths
1800
x5658
2008G
Sakurako's Task
binary search
,
greedy
,
math
,
number theory
1800
x5210
2006B
Iris and the Tree
brute force
,
data structures
,
dfs and similar
,
dsu
,
math
,
trees
1800
x3365
2005C
Lazy Narek
dp
,
implementation
,
strings
1800
x7096
1995C
Squaring
brute force
,
constructive algorithms
,
greedy
,
implementation
,
math
,
number theory
1800
x8644
1990D
Grid Puzzle
bitmasks
,
brute force
,
dp
,
greedy
,
implementation
1800
x6360
1987D
World is Mine
dp
,
games
1800
x7218
1981C
Turtle and an Incomplete Sequence
bitmasks
,
brute force
,
constructive algorithms
,
greedy
,
implementation
,
math
1800
x5401
1979D
Fixing a Binary String
bitmasks
,
brute force
,
constructive algorithms
,
dp
,
greedy
,
hashing
,
strings
1800
x6698
1974E
Money Buys Happiness
dp
1800
x8130
1970E1
Trails (Easy)
dp
1800
x2270
1968F
Equal XOR Segments
binary search
,
data structures
1800
x5575
1965B
Missing Subsequence Sum
bitmasks
,
constructive algorithms
,
greedy
,
number theory
1800
x6810
1955F
Unfair Game
dp
,
games
,
greedy
,
math
,
schedules
1800
x7206
1954D
Colored Balls
combinatorics
,
dp
,
math
,
sortings
1800
x6276
1949I
Disks
dfs and similar
,
geometry
,
graph matchings
,
graphs
1800
x1904
1941F
Rudolf and Imbalance
binary search
,
greedy
,
sortings
,
two pointers
1800
x6142
1935D
Exam in MAC
binary search
,
combinatorics
,
implementation
,
math
1800
x8358
1935C
Messenger in MAC
binary search
,
brute force
,
constructive algorithms
,
data structures
,
dp
,
greedy
,
sortings
1800
x8298
1930D1
Sum over all Substrings (Easy Version)
brute force
,
dp
,
greedy
,
strings
1800
x4183
1923D
Slimes
binary search
,
constructive algorithms
,
data structures
,
greedy
,
two pointers
1800
x6943
1922E
Increasing Subsequences
bitmasks
,
constructive algorithms
,
divide and conquer
,
greedy
,
math
1800
x7841
1915G
Bicycles
graphs
,
greedy
,
implementation
,
shortest paths
,
sortings
1800
x6579
1912K
Kim's Quest
bitmasks
,
combinatorics
,
dp
1800
x2608
1910D
Remove and Add
*special problem
,
greedy
1800
x362
1907F
Shift and Reverse
greedy
,
sortings
1800
x4991
1904D2
Set To Max (Hard Version)
constructive algorithms
,
data structures
,
divide and conquer
,
greedy
,
implementation
,
sortings
1800
x4539
1872F
Selling a Menagerie
dfs and similar
,
dsu
,
graphs
,
implementation
,
math
1800
x6473
1870D
Prefix Purchase
greedy
,
implementation
,
sortings
1800
x7115
1867D
Cyclic Operations
brute force
,
constructive algorithms
,
dfs and similar
,
graphs
,
greedy
,
implementation
1800
x5895
1862F
Magic Will Save the World
binary search
,
bitmasks
,
brute force
,
dp
1800
x6401
1861D
Sorting By Multiplication
dp
,
greedy
1800
x6909
1859D
Andrey and Escape from Capygrad
binary search
,
data structures
,
dp
,
dsu
,
greedy
,
sortings
1800
x7119
1856E1
PermuTree (easy version)
dfs and similar
,
dp
,
trees
1800
x5447
1852B
Imbalanced Arrays
constructive algorithms
,
graphs
,
greedy
,
math
,
sortings
,
two pointers
1800
x4558
1852A
Ntarsis' Set
binary search
,
math
,
number theory
1800
x8182
1851F
Lisa and the Martians
bitmasks
,
greedy
,
math
,
strings
,
trees
1800
x5978
1848C
Vika and Price Tags
math
,
number theory
1800
x6386
1846F
Rudolph and Mimic
constructive algorithms
,
implementation
,
interactive
1800
x3176
1846E2
Rudolf and Snowflakes (hard version)
binary search
,
brute force
,
implementation
,
math
1800
x7131
1845D
Rating System
binary search
,
brute force
,
data structures
,
dp
,
dsu
,
greedy
,
math
,
two pointers
1800
x7954
1843F1
Omsk Metro (simple version)
data structures
,
dfs and similar
,
dp
,
graphs
,
greedy
,
math
,
trees
1800
x5405
1841C
Ranom Numbers
brute force
,
dp
,
greedy
,
math
,
strings
1800
x7942
1833G
Ksyusha and Chinchilla
constructive algorithms
,
dfs and similar
,
dp
,
dsu
,
greedy
,
implementation
,
trees
1800
x5483
1824B1
LuoTianyi and the Floating Islands (Easy Version)
combinatorics
,
math
,
probabilities
,
trees
1800
x4707
1809D
Binary String Sorting
constructive algorithms
,
greedy
1800
x6417
1805D
A Wide, Wide Graph
dfs and similar
,
dp
,
graphs
,
greedy
,
trees
1800
x6782
1801B
Buying gifts
data structures
,
greedy
,
sortings
1800
x6400
1793D
Moscow Gorillas
binary search
,
dp
,
greedy
,
implementation
,
math
,
two pointers
1800
x6300
1781D
Many Perfect Squares
brute force
,
math
,
number theory
1800
x5568
1780D
Bit Guessing Game
binary search
,
bitmasks
,
constructive algorithms
,
interactive
1800
x5028
1775D
Friendly Spiders
dfs and similar
,
graphs
,
math
,
number theory
,
shortest paths
1800
x6400
1769D1
Игра в Девятку I
*special problem
,
brute force
,
dp
1800
x384
1768D
Lucky Permutation
constructive algorithms
,
dfs and similar
,
graphs
,
greedy
1800
x7279
1759F
All Possible Digits
binary search
,
data structures
,
greedy
,
math
,
number theory
1800
x3977
1758D
Range = √Sum
binary search
,
brute force
,
constructive algorithms
,
math
,
two pointers
1800
x7423
1750D
Count GCD
combinatorics
,
math
,
number theory
1800
x6033
1740E
Hanging Hearts
constructive algorithms
,
data structures
,
dfs and similar
,
dp
,
greedy
,
trees
1800
x4404
1734D
Slime Escape
data structures
,
dp
,
greedy
,
two pointers
1800
x6385
1732C1
Sheikh (Easy version)
binary search
,
bitmasks
,
greedy
,
two pointers
1800
x6008
1729E
Guess the Cycle Size
interactive
,
probabilities
1800
x7114
1728D
Letter Picking
constructive algorithms
,
dp
,
games
,
two pointers
1800
x7348
1725M
Moving Both Hands
dp
,
graphs
,
shortest paths
1800
x3182
1725H
Hot Black Hot White
constructive algorithms
,
math
1800
x2665
1721D
Maximum AND
bitmasks
,
dfs and similar
,
divide and conquer
,
greedy
,
sortings
1800
x6739
1720D1
Xor-Subsequence (easy version)
bitmasks
,
brute force
,
dp
,
strings
,
trees
,
two pointers
1800
x6073
1718A1
Burenka and Traditions (easy version)
dp
,
greedy
1800
x5858
1713D
Tournament Countdown
constructive algorithms
,
greedy
,
interactive
,
number theory
,
probabilities
1800
x5729
1709C
Recover an RBS
constructive algorithms
,
greedy
,
implementation
,
strings
1800
x8934
1705D
Mark and Lightbulbs
combinatorics
,
constructive algorithms
,
greedy
,
math
,
sortings
1800
x6389
1691D
Max GEQ Sum
binary search
,
constructive algorithms
,
data structures
,
divide and conquer
,
implementation
,
two pointers
1800
x5888
1678B2
Tokitsukaze and Good 01-String (hard version)
dp
,
greedy
,
implementation
1800
x6682
1675F
Vlad and Unfinished Business
dfs and similar
,
dp
,
greedy
,
trees
1800
x5410
1674F
Desktop Rearrangement
data structures
,
greedy
,
implementation
1800
x5106
1666L
Labyrinth
dfs and similar
,
graphs
1800
x3177
1666C
Connect the Points
brute force
,
constructive algorithms
,
geometry
1800
x3231
1648B
Integral Array
brute force
,
constructive algorithms
,
data structures
,
math
1800
x6504
1637D
Yet Another Minimization Problem
dp
,
greedy
,
math
1800
x7831
1635D
Infinite Set
bitmasks
,
dp
,
math
,
matrices
,
number theory
,
strings
1800
x6320
1630B
Range and Partition
binary search
,
constructive algorithms
,
data structures
,
greedy
,
two pointers
1800
x5811
1620C
BA-String
brute force
,
dp
,
greedy
,
implementation
,
math
1800
x6619
1619D
New Year's Problem
binary search
,
greedy
,
sortings
1800
x7654
1617D1
Too Many Impostors (easy version)
constructive algorithms
,
implementation
,
interactive
1800
x4735
1611F
ATM and Students
binary search
,
data structures
,
two pointers
1800
x6532
1583D
Omkar and the Meaning of Life
constructive algorithms
,
greedy
,
interactive
1800
x5438
1582F1
Korney Korneevich and XOR (easy version)
bitmasks
,
dp
,
greedy
1800
x5718
1575D
Divisible by Twenty-Five
brute force
,
dfs and similar
,
dp
1800
x2609
1572A
Book
binary search
,
brute force
,
data structures
,
dp
,
graphs
,
implementation
,
sortings
1800
x9151
1571D
Sweepstake
*special problem
,
brute force
,
constructive algorithms
,
implementation
,
math
1800
x335
1571C
Rhyme
*special problem
,
implementation
1800
x380
1560E
Polycarp and String Transformation
binary search
,
implementation
,
sortings
,
strings
1800
x8118
1556D
Take a Guess
bitmasks
,
constructive algorithms
,
interactive
,
math
1800
x7087
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