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Hot problems
COCI '08 Contest 4 #6 Periodni
CCC '24 J4 - Troublesome Keys
CCC '24 S2 - Heavy-Light Composition
COCI '23 Contest 5 #1 Zlagalica
COCI '23 Contest 5 #4 Rolete
APIO '09 P1 - Digging for Oil
COCI '22 Contest 4 #1 7Krokods
Problem
Category
Points ▾
AC %
Users
COCI '21 Contest 3 #4 Ekoeko
COCI
15p
33.1%
40
An Animal Contest 5 P5 - Counting Rectangles
AAC
15p
12.3%
50
Liars
Uncategorized
15p
15.8%
9
COI '18 #2 Ljepotica
COCI
15p
26.7%
7
Baltic OI '07 P5 - Connected Points
Baltic OI
15p
28.0%
6
Mock CCC '22 2 S4 - Kaguya Wants to Build a Great Wall
Mock CCC
15p
7.5%
8
Baltic OI '08 P2 - Gates
Baltic OI
15p
16.7%
1
Baltic OI '10 P1 - BEARs
Baltic OI
15
30.4%
5
The Contest Contest 1 P3 - A Typical WAC Problem
Uncategorized
15p
17.4%
47
Baltic OI '10 P6 - Mines
Baltic OI
15p
9.1%
1
DMOPC '21 Contest 6 P4 - Colourful Paths
DMOPC
15p
9.1%
98
Baltic OI '11 P4 - Treasures and Vikings
Baltic OI
15p
37.7%
18
Yet Another Contest 2 P4 - No More Arithmetic
YAC
15p
15.1%
51
COI '19 #4 Zagrade
COCI
15p
21.5%
17
CCC '22 S4 - Good Triplets
CCC
15p
28.4%
308
Baltic OI '15 P3 - Network
Baltic OI
15p
25.7%
17
Baltic OI '15 P5 - Hacker
Baltic OI
15p
42.5%
13
COI '14 #2 Kovanice
COCI
15p
12.2%
18
Yet Another Contest 3 P3 - Topography
YAC
15p
2.4%
17
Yet Another Contest 3 P4 - Rumour
YAC
15p
26.2%
69
Another Random Contest 1 P6 - Smash Bros
Uncategorized
15p
20.3%
15
Another Random Contest 1 P5 - A Strange Country
Uncategorized
15p
19.2%
32
Another Random Contest 1 P4 - Bracket Query
Uncategorized
15p
44.3%
34
Comparing Arrays
Uncategorized
15p
17.0%
62
Cheerio Contest 1 S5 - Coin Game
Uncategorized
15p
46.4%
35
Levve Loves Segment Trees
Uncategorized
15
13.4%
35
Baltic OI '03 P5 - Lamps
Baltic OI
15p
29.9%
17
Spy Tree
Uncategorized
15p
21.9%
19
A Math Contest P11 - Weak Goldbach's Conjecture
Uncategorized
15
23.9%
58
Baltic OI '13 P4 - Brunhilda's Birthday
Baltic OI
15p
27.0%
10
NOIP '20 P3 - Game of Moving Ball
China NOI
15p
12.3%
6
NOI '02 P2 - Naughty Kid
China NOI
15p
22.5%
14
Baltic OI '14 P5 - Portals
Baltic OI
15p
23.4%
16
Baltic OI '14 P6 - Senior Postmen
Baltic OI
15p
19.8%
14
SGS Programming Challenge P3 - Tree in Biology Class
Uncategorized
15p
16.5%
39
Baltic OI '12 P1 - Brackets
Baltic OI
15p
32.7%
12
Baltic OI '12 P2 - Mobile
Baltic OI
15p
15.2%
8
Yet Another Contest 6 P5 - No More Coyotes
YAC
15p
22.5%
25
JOI '20 Open P3 - Power Plant
JOI
15p
40.9%
22
CEOI '22 P2 - Homework
CEOI
15p
45.3%
68
Baltic OI '01 P5 - Mars Maps
Baltic OI
15p
13.6%
28
DMOPC '22 Contest 3 P3 - Ina's Takodachis
DMOPC
15p
5.7%
58
Waterloo 2022 Fall B - Lightbulbs
Waterloo Local
15
19.3%
15
EGOI '22 P2 - Lego Wall
EGOI
15p
11.9%
16
EGOI '22 P3 - Social Engineering
EGOI
15p
6.6%
14
Max's Anger Contest Series 1 P5 - Slacking Subsequences
Seasonal
15p
30.9%
58
COCI '22 Contest 1 #5 Neboderi
COCI
15p
27.4%
46
DMOPC '22 Contest 4 P3 - K-Knight
DMOPC
15
16.0%
42
NOIP '04 P4 - Bugs Eating Computation
China NOI
15p
5.5%
9
NOIP '07 P3 - Removing Numbers from Matrix
China NOI
15p
20.4%
22
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