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Before contest
Codeforces Round 987 (Div. 2)
05:56:28
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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
hashing
implementation
interactive
math
matrices
meet-in-the-middle
number theory
probabilities
schedules
shortest paths
sortings
string suffix structures
strings
ternary search
trees
two pointers
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Problems
#
Name
1797E
Li Hua and Array
brute force
,
data structures
,
dsu
,
math
,
number theory
,
two pointers
2300
x1301
1797D
Li Hua and Tree
brute force
,
data structures
,
dfs and similar
,
dp
,
implementation
,
trees
1900
x4027
1797C
Li Hua and Chess
constructive algorithms
,
greedy
,
interactive
1600
x7754
1796F
Strange Triples
brute force
,
math
,
number theory
2900
x175
1796E
Colored Subgraphs
dfs and similar
,
dp
,
games
,
greedy
,
trees
2500
x772
1796D
Maximum Subarray
data structures
,
dp
,
greedy
,
two pointers
2000
x4418
1796C
Maximum Set
binary search
,
math
1600
x10550
1795G
Removal Sequences
bitmasks
,
dfs and similar
,
graphs
2700
x690
1795F
Blocking Chips
binary search
,
constructive algorithms
,
dfs and similar
,
greedy
,
trees
2400
x1121
1795E
Explosions?
binary search
,
data structures
,
dp
,
greedy
,
math
2200
x2061
1795D
Triangle Coloring
combinatorics
,
math
1600
x9299
1795C
Tea Tasting
binary search
,
data structures
,
implementation
1500
x12758
1794E
Labeling the Tree with Distances
data structures
,
dp
,
greedy
,
hashing
,
implementation
,
trees
2400
x1115
1794D
Counting Factorizations
combinatorics
,
divide and conquer
,
dp
,
math
,
number theory
1900
x3622
1793F
Rebrending
brute force
,
data structures
,
divide and conquer
,
implementation
2600
x1409
1793E
Velepin and Marketing
binary search
,
data structures
,
dp
,
greedy
,
sortings
,
two pointers
2600
x1101
1793D
Moscow Gorillas
binary search
,
dp
,
greedy
,
implementation
,
math
,
two pointers
1800
x6265
1792F2
Graph Coloring (hard version)
brute force
,
combinatorics
,
divide and conquer
,
dp
,
fft
,
graphs
2900
x398
1792F1
Graph Coloring (easy version)
combinatorics
,
dp
,
graphs
2700
x739
1792E
Divisors and Table
brute force
,
dfs and similar
,
dp
,
number theory
2400
x1395
1792D
Fixed Prefix Permutations
binary search
,
bitmasks
,
data structures
,
hashing
,
math
,
sortings
1700
x6326
1792C
Min Max Sort
binary search
,
brute force
,
greedy
,
math
,
two pointers
1500
x14285
1791G2
Teleporters (Hard Version)
binary search
,
greedy
,
sortings
1900
x4836
1791F
Range Update Point Query
binary search
,
brute force
,
data structures
1500
x12611
1790G
Tokens on Graph
constructive algorithms
,
dfs and similar
,
graphs
,
shortest paths
2300
x1134
1790F
Timofey and Black-White Tree
brute force
,
dfs and similar
,
divide and conquer
,
graphs
,
greedy
,
math
,
shortest paths
,
trees
2100
x3385
1790E
Vlad and a Pair of Numbers
bitmasks
,
constructive algorithms
1400
x15317
1789F
Serval and Brain Power
bitmasks
,
brute force
,
dp
,
greedy
,
implementation
,
strings
2700
x725
1789E
Serval and Music Game
brute force
,
dp
,
implementation
,
math
,
number theory
2500
x823
1789D
Serval and Shift-Shift-Shift
bitmasks
,
brute force
,
constructive algorithms
,
implementation
2200
x1697
1789C
Serval and Toxel's Arrays
combinatorics
,
dp
,
implementation
,
math
1500
x8651
1788F
XOR, Tree, and Queries
bitmasks
,
constructive algorithms
,
dfs and similar
,
dsu
,
graphs
,
greedy
,
implementation
,
trees
2500
x862
1788E
Sum Over Zero
data structures
,
dfs and similar
,
dp
2200
x2720
1788D
Moving Dots
binary search
,
brute force
,
combinatorics
,
math
,
two pointers
2000
x3960
1787I
Treasure Hunt
data structures
,
divide and conquer
,
two pointers
3400
x221
1787H
Codeforces Scoreboard
binary search
,
data structures
,
dp
,
geometry
3300
x237
1787G
Colorful Tree Again
brute force
,
data structures
,
trees
3000
x439
1787F
Inverse Transformation
constructive algorithms
,
implementation
,
math
2500
x690
1787E
The Harmonization of XOR
bitmasks
,
constructive algorithms
,
greedy
,
math
2100
x2370
1787D
Game on Axis
combinatorics
,
dfs and similar
,
dsu
,
graphs
,
implementation
1900
x3426
1787C
Remove the Bracket
dp
,
greedy
,
math
1600
x7157
1784F
Minimums or Medians
3400
x254
1784E
Infinite Game
brute force
,
combinatorics
,
dp
,
games
,
probabilities
3100
x346
1784D
Wooden Spoon
combinatorics
,
dp
2400
x1036
1784C
Monsters (hard version)
data structures
,
greedy
2200
x1682
1784B
Letter Exchange
constructive algorithms
1900
x3358
1783G
Weighed Tree Radius
data structures
,
divide and conquer
,
implementation
,
trees
2800
x480
1783F
Double Sort II
dfs and similar
,
flows
,
graph matchings
,
graphs
2500
x1036
1783E
Game of the Year
brute force
,
data structures
,
math
,
number theory
2300
x2123
1783D
Different Arrays
brute force
,
dp
,
implementation
2000
x4495
1783C
Yet Another Tournament
binary search
,
greedy
,
sortings
1700
x9403
1781H2
Window Signals (hard version)
3500
x97
1781H1
Window Signals (easy version)
3200
x119
1781G
Diverse Coloring
constructive algorithms
,
trees
3200
x232
1781F
Bracket Insertion
combinatorics
,
dp
,
math
,
trees
2700
x911
1781E
Rectangle Shrinking
binary search
,
brute force
,
data structures
,
greedy
,
implementation
,
two pointers
2300
x1309
1781D
Many Perfect Squares
brute force
,
math
,
number theory
1800
x5552
1781C
Equal Frequencies
brute force
,
constructive algorithms
,
greedy
,
implementation
,
sortings
,
strings
1600
x7721
1780G
Delicious Dessert
binary search
,
dsu
,
hashing
,
math
,
number theory
,
string suffix structures
2400
x752
1780F
Three Chairs
bitmasks
,
brute force
,
combinatorics
,
data structures
,
dp
,
number theory
,
sortings
2300
x1507
1780E
Josuke and Complete Graph
binary search
,
brute force
,
data structures
,
math
,
number theory
2400
x1459
1780D
Bit Guessing Game
binary search
,
bitmasks
,
constructive algorithms
,
interactive
1800
x5004
1779H
Olympic Team Building
brute force
,
meet-in-the-middle
3500
x144
1779G
The Game of the Century
constructive algorithms
,
graphs
,
shortest paths
3000
x321
1779F
Xorcerer's Stones
bitmasks
,
constructive algorithms
,
dp
,
trees
2500
x1266
1779E
Anya's Simultaneous Exhibition
constructive algorithms
,
graphs
,
greedy
,
interactive
,
sortings
2400
x1801
1779D
Boris and His Amazing Haircut
constructive algorithms
,
data structures
,
dp
,
dsu
,
greedy
,
sortings
1700
x7980
1779C
Least Prefix Sum
data structures
,
greedy
1600
x12493
1778F
Maximizing Root
dfs and similar
,
dp
,
graphs
,
math
,
number theory
,
trees
2600
x673
1778E
The Tree Has Fallen!
bitmasks
,
dfs and similar
,
math
,
trees
2500
x898
1778D
Flexible String Revisit
combinatorics
,
dp
,
math
,
probabilities
2100
x2820
1778C
Flexible String
bitmasks
,
brute force
,
strings
1600
x8348
1777F
Comfortably Numb
bitmasks
,
data structures
,
divide and conquer
,
strings
,
trees
2400
x965
1777E
Edge Reverse
binary search
,
dfs and similar
,
graphs
,
trees
2200
x1882
1777D
Score of a Tree
bitmasks
,
combinatorics
,
dfs and similar
,
dp
,
math
,
probabilities
,
trees
1900
x3548
1777C
Quiz Master
binary search
,
math
,
number theory
,
sortings
,
two pointers
1700
x8726
1776N
Count Permutations
math
3500
x83
1776M
Parmigiana With Seafood
binary search
,
dp
,
greedy
,
trees
3000
x377
1776L
Controllers
binary search
,
math
1500
x6207
1776K
Uniform Chemistry
dp
,
math
3200
x69
1776J
Italian Data Centers
graphs
,
shortest paths
2500
x703
1776I
Spinach Pizza
games
,
geometry
,
greedy
,
interactive
2500
x686
1776G
Another Wine Tasting Event
combinatorics
,
constructive algorithms
,
math
,
strings
2100
x2079
1776F
Train Splitting
constructive algorithms
,
graphs
,
greedy
1700
x3515
1776E
Crossing the Railways
data structures
,
dp
3500
x73
1776D
Teamwork
constructive algorithms
,
greedy
,
math
2800
x370
1776C
Library game
games
,
greedy
,
interactive
,
sortings
2500
x813
1776B
Vittorio Plays with LEGO Bricks
dp
,
geometry
2200
x1361
1775F
Laboratory on Pluto
constructive algorithms
,
dp
,
greedy
,
math
2500
x769
1775E
The Human Equation
greedy
,
implementation
2100
x3236
1775D
Friendly Spiders
dfs and similar
,
graphs
,
math
,
number theory
,
shortest paths
1800
x6362
1775C
Interesting Sequence
bitmasks
,
math
1600
x10630
1774H
Maximum Permutation
constructive algorithms
3500
x135
1774G
Segment Covering
brute force
,
combinatorics
,
constructive algorithms
,
data structures
,
dp
,
trees
3200
x441
1774F2
Magician and Pigs (Hard Version)
binary search
,
brute force
,
data structures
,
implementation
2700
x713
1774F1
Magician and Pigs (Easy Version)
brute force
,
data structures
,
implementation
2400
x1085
1774E
Two Chess Pieces
dfs and similar
,
dp
,
greedy
,
trees
1900
x3524
1774D
Same Count One
brute force
,
constructive algorithms
,
greedy
,
implementation
,
two pointers
1600
x7961
1774B
Coloring
constructive algorithms
,
greedy
,
math
1500
x12390
1773L
Lisa's Sequences
dp
3500
x44
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