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Codeforces Round 991 (Div. 3)
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combine-tags-by-or
*combine tags by OR
2-sat
binary search
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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implementation
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Problems
#
Name
2045M
Mirror Maze
brute force
,
dfs and similar
,
graphs
,
implementation
1800
x640
2039C2
Shohag Loves XOR (Hard Version)
bitmasks
,
brute force
,
math
,
number theory
1800
x3437
2035D
Yet Another Real Number Problem
binary search
,
data structures
,
divide and conquer
,
greedy
,
implementation
,
math
1800
x4545
2033F
Kosuke's Sloth
brute force
,
math
,
number theory
1800
x5327
2032D
Genokraken
constructive algorithms
,
data structures
,
graphs
,
greedy
,
implementation
,
interactive
,
trees
,
two pointers
1800
x4657
2025D
Attribute Checks
brute force
,
data structures
,
dp
,
implementation
,
math
,
two pointers
1800
x5987
2022C
Gerrymandering
dp
,
implementation
1800
x3959
2020D
Connect the Dots
brute force
,
dp
,
dsu
,
graphs
,
math
,
trees
1800
x5715
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
x5211
2006B
Iris and the Tree
brute force
,
data structures
,
dfs and similar
,
dsu
,
math
,
trees
1800
x3365
2005C
Lazy Narek
dp
,
implementation
,
strings
1800
x7097
1995C
Squaring
brute force
,
constructive algorithms
,
greedy
,
implementation
,
math
,
number theory
1800
x8644
1990D
Grid Puzzle
bitmasks
,
brute force
,
dp
,
greedy
,
implementation
1800
x6361
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
x6699
1974E
Money Buys Happiness
dp
1800
x8133
1970E1
Trails (Easy)
dp
1800
x2270
1968F
Equal XOR Segments
binary search
,
data structures
1800
x5576
1965B
Missing Subsequence Sum
bitmasks
,
constructive algorithms
,
greedy
,
number theory
1800
x6811
1955F
Unfair Game
dp
,
games
,
greedy
,
math
,
schedules
1800
x7207
1954D
Colored Balls
combinatorics
,
dp
,
math
,
sortings
1800
x6279
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
x4993
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
x7116
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
x5980
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
x7132
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
x7944
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
x6418
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
x6301
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
x6036
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
x6741
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
x5411
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
x5719
1575D
Divisible by Twenty-Five
brute force
,
dfs and similar
,
dp
1800
x2610
1572A
Book
binary search
,
brute force
,
data structures
,
dp
,
graphs
,
implementation
,
sortings
1800
x9152
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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