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Hot problems
Educational DP Contest AtCoder C - Vacation
CCCHK '15 J3 - Queens can't attack me!
COCI '14 Contest 5 #3 Traktor
IOI '04 P4 - Phidias
CCC '10 J2 - Up and Down
IOI '14 Practice Task 1 - Square
CCC '24 J5 - Harvest Waterloo
Problem
Category
Points
AC % ▴
Users
NOI '16 P3 - The Beauty of Cycles
China NOI
30p
3.4%
1
IOI '23 P6 - Robot Contest
IOI
40p
3.4%
2
Calendar Contest Problem 6 — Ming Dynasty
Seasonal
25
3.5%
2
IOIQR P5 - Some Game
Seasonal
25
3.5%
3
OCC '19 G4 - Willson and Fighting
Olympiads School
30p
3.5%
3
IOI '11 P6 - Parrots
IOI
20p
3.6%
16
WC '15 Contest 3 S4 - Lex Luthor's Landmines
Woburn Challenge
30p
3.6%
6
Valentine's Day '15 P1 - #1 BABE
Seasonal
15p
3.6%
2
DMOPC '21 Contest 10 P4 - Bitwise Telephone
DMOPC
17p
3.7%
30
CCO Preparation Test 2 P2 - Forest Area
Mock CCO
25p
3.8%
5
Cheerio Contest 3 P5 - Train Network
Uncategorized
20p
3.8%
15
Yet Another Contest 4 P4 - Even The Odds
YAC
20p
3.8%
11
CCC '20 J4 - Cyclic Shifts (Hard)
CCC
12p
3.8%
36
TLE '16 Contest 6 (Mock CCC) S5 - Toll Routes
TLE
20p
3.9%
26
COI '19 #2 Pastiri
COCI
35p
3.9%
4
Mock CCC '15 S5 - Kongou
Mock CCC
40p
3.9%
13
Mock CCC '23 2 S3 - Richard The Penguin
Mock CCC
10p
3.9%
13
CCO '06 P5 - Domino
CCO
30
3.9%
3
Baltic OI '18 P3 - Worm Worries
Baltic OI
30p
4.0%
5
CCC '00 S5 - Sheep and Coyotes
CCC
10p
4.0%
167
A Floyd-Warshall Problem
Uncategorized
15
4.0%
2
COCI '16 Contest 7 #5 Paralelogrami
COCI
17p
4.0%
2
EGOI '23 P8 - Guessing Game
EGOI
50p
4.0%
7
Maximum Deviation Spanning Tree
Olympiads School
20p
4.0%
4
NOI '02 P5 - New Tetris
China NOI
15p
4.1%
3
Triway Cup '19 Summer D - Napping
Seasonal
15p
4.1%
6
COI '17 #4 Zagonetka
COCI
17p
4.1%
2
COCI '22 Contest 5 #5 Zastave
COCI
17p
4.1%
20
ETSR '23 Onsite Round 2 Problem 2 - Exponents
Uncategorized
25p
4.1%
13
Another Contest 1 Problem 3 - Poutine
ACC
10
4.1%
57
CCC '00 S5 - Sheep and Coyotes (Hard)
CCC
20
4.1%
18
Bubble Cup V8 G Run for beer
Bubble Cup
20
4.1%
17
HCI '16 - Computation
Uncategorized
0
4.2%
3
The Contest Contest 1 P5 - A Typical CCO Problem
Uncategorized
20p
4.2%
24
DMOPC '18 Contest 4 P6 - Dr. Henri and Resistor Chains
DMOPC
20p
4.2%
10
ETSR '23 Onsite Round 1 Problem 1 - Arithmetic
Uncategorized
20p
4.3%
16
CCO '99 P5 - Sum Of Products
CCO
15
4.3%
1
Mock CCO '19 Contest 2 Problem 5 - A Geometry Problem
Mock CCO
12p
4.3%
2
Root Solver
Uncategorized
30p
4.4%
9
MNYC '17: Skiing Competition
Seasonal
15p
4.4%
7
ETSR '23 Online Round 2 Problem 2 - Equation
Uncategorized
15p
4.4%
35
SMAC 08/09 (Oct) #4 - Daycare
Uncategorized
15p
4.5%
20
Waterloo 2023 Winter E - Colourful Tree
Waterloo Local
25
4.5%
4
DMOPC '21 Contest 4 P6 - Balanced Line
DMOPC
35p
4.5%
4
CCO '04 P3 - S and K
CCO
15p
4.5%
6
Waterloo 2023 Fall E - Loose Goose
Waterloo Local
25
4.5%
1
IOI '23 P1 - Closing Time
IOI
25p
4.6%
20
IOI '23 P3 - Soccer Stadium
IOI
30p
4.7%
12
CCO '21 P6 - Loop Town
CCO
50p
4.7%
13
VPEX P3 - Coding Club
Uncategorized
12p
4.7%
25
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