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Hot problems
CCC '24 J4 - Troublesome Keys
COCI '22 Contest 4 #1 7Krokods
CCC '24 S2 - Heavy-Light Composition
CCC '19 J3 - Cold Compress
CCC '24 J5 - Harvest Waterloo
COCI '23 Contest 5 #1 Zlagalica
CCC '24 S3 - Swipe
Problem
Category
Points
AC %
Users ▾
DWITE '02 R2 #1 - Sales!
DWITE
5
31.8%
91
COCI '13 Contest 5 #1 Lozinka
COCI
3p
52.2%
91
SAC '22 Code Challenge 4 P4 - Obligatory Subarray Problem
SAC Coding Challenge
10p
22.6%
91
Magic Sequence
Olympiads School
7p
64.8%
91
IOI '13 P5 - Robots
IOI
20p
18.3%
90
VMSS Pre-Pre-Windsor P4 - The New Kid
Uncategorized
3
23.0%
90
Strategic Arrays
Uncategorized
15p
32.2%
90
IOI '02 P2 - Utopia Divided
IOI
20p
24.3%
90
COCI '09 Contest 5 #1 Sok
COCI
3
53.8%
90
Hard Question
Uncategorized
5
62.6%
90
COCI '20 Contest 6 #3 Anagramistica
COCI
12p
44.6%
90
Age Demographic
Uncategorized
5
25.4%
90
JOI '14 Open P5 - Pinball
JOI
25p
26.0%
89
JOI '13 Open P3 - Watching
JOI
15p
29.7%
89
GFSSOC '15 Fall S3 - System(0);
GFSSOC
10p
22.6%
89
CCO '16 P2 - Splitting Hares
CCO
15p
14.2%
89
Mock CCC '18 Contest 2 S5 - A Link/Cut Tree Problem
Mock CCC
15p
23.1%
89
Valentine's Day '19 J5 - Falling in Love
Uncategorized
7p
14.0%
89
CCO '96 P2 - SafeBreaker
CCO
10
36.2%
89
DWITE '02 R2 #3 - The Game of Life
DWITE
7
54.0%
89
COCI '21 Contest 2 #1 Kaučuk
COCI
5p
75.2%
89
Yet Another Contest 7 P3 - No More Math Homework
YAC
12p
16.2%
89
DMOPC '22 Contest 4 P2 - Fake Painting
DMOPC
10p
18.5%
89
COCI '22 Contest 4 #1 7Krokods
COCI
5p
59.6%
89
ECOO '13 R1 P3 - Hexudoku
ECOO
7p
52.7%
88
Facebook Hacker Cup '15 Round 1 P4 - Corporate Gifting
FHC
17
46.0%
88
ECOO '16 R2 P1 - Palindrome Panic
ECOO
12p
14.7%
88
DMPG '18 B4 - Shimnanigans
DMOPC
5p
27.7%
88
COCI '15 Contest 5 #4 Poplava
COCI
12
33.2%
88
Triway Cup '19 Summer F - Race
Seasonal
3
39.0%
88
James' Rectangles
Uncategorized
10p
33.5%
88
DMOPC '20 Contest 1 P5 - Victor Takes Over Canada
DMOPC
17p
11.2%
88
CCO '20 P4 - Travelling Salesperson
CCO
25p
19.3%
88
2048
Uncategorized
15
3.1%
88
IOI '13 P2 - Art Class (Standard I/O)
IOI
20p
2.7%
88
UCRPC F21 A - Senseless Census
ICPC
5
65.5%
88
RGPC '17 P4 - Snow Day
Uncategorized
10p
13.6%
87
COCI '07 Contest 5 #4 Avogadro
COCI
15p
27.7%
87
DWITE '09 R2 #2 - Mini DWITE
DWITE
3
31.5%
87
DWITE '12 R1 #1 - Candy Piles
DWITE
3
35.9%
87
UTS Open '18 P4 - Ianine's Lil Lab
Uncategorized
10p
28.8%
87
CCO '19 P1 - Human Error
CCO
10p
31.2%
87
COCI '09 Contest 3 #3 Sort
COCI
5
44.5%
87
NOI '04 P1 - The Depressed Cashier
China NOI
20p
15.3%
87
WC '18 Contest 3 J3 - R
Woburn Challenge
3p
73.0%
87
WC '15 Contest 3 J2 - Electroshock Therapy
Woburn Challenge
5
52.4%
87
WC '01 P6 - Mission Impossible 3
Woburn Challenge
5p
17.7%
87
Wesley's Anger Contest 6 Problem 4 - Runway Lights
WAC
12p
14.0%
87
BSSPC '22 P7 - Exec Team Applications
Uncategorized
10p
22.9%
87
COCI '22 Contest 5 #1 Kalendar
COCI
5p
44.3%
87
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