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Hot problems
CCC '25 J3 - Product Codes
CCC '25 J4 - Sunny Days
CCC '25 J5 - Connecting Territories
Problem
Category
Points
AC %
Users
IOI '19 P6 - Sky Walking
IOI
40p
9.5%
12
IOI '20 P1 - Comparing Plants
IOI
40p
6.2%
19
IOI '20 P2 - Connecting Supertrees
IOI
15p
13.7%
70
IOI '20 P3 - Carnival Tickets
IOI
20p
12.1%
45
IOI '20 P4 - Packing Biscuits
IOI
25p
13.7%
18
IOI '20 P5 - Counting Mushrooms
IOI
35p
3.4%
5
IOI '20 P6 - Stations
IOI
20p
13.1%
25
IOI '21 P1 - Distributing Candies
IOI
30p
14.0%
37
IOI '21 P2 - Keys
IOI
25p
9.9%
15
IOI '21 P3 - Fountain Parks
IOI
30p
5.3%
8
IOI '21 P4 - Mutating DNA
IOI
12p
30.0%
88
IOI '21 P5 - Dungeons Game
IOI
30p
6.7%
11
IOI '21 P6 - Bit Shift Registers
IOI
30p
13.5%
10
IOI '22 P1 - Catfish Farm
IOI
25p
8.0%
59
IOI '22 P2 - Prisoner Challenge
IOI
25p
7.7%
26
IOI '22 P3 - Radio Towers
IOI
30p
7.0%
17
IOI '22 P4 - Digital Circuit
IOI
25p
24.5%
37
IOI '22 P5 - Rarest Insects
IOI
30p
5.6%
27
IOI '22 P6 - Thousands Islands
IOI
30p
3.3%
7
IOI '23 P1 - Closing Time
IOI
25p
4.1%
25
IOI '23 P2 - Longest Trip
IOI
25p
3.5%
18
IOI '23 P3 - Soccer Stadium
IOI
30p
5.0%
16
IOI '23 P4 - Beech Tree
IOI
35p
3.2%
3
IOI '23 P5 - Overtaking
IOI
25p
5.6%
14
IOI '23 P6 - Robot Contest
IOI
40p
8.3%
6
IOI '24 P1 - Nile
IOI
15p
12.4%
52
IOI '24 P2 - Message
IOI
40p
9.6%
19
IOI '24 P3 - Tree
IOI
30p
2.8%
5
IOI '24 P4 - Hieroglyphs
IOI
35p
3.8%
2
IOI '24 P5 - Mosaic
IOI
20p
12.4%
18
IOI '24 P6 - Sphinx's Riddle
IOI
25p
8.0%
2
IOI '94 P1 - The Triangle
IOI
7p
56.6%
1564
IOI '94 P2 - The Castle
IOI
10
18.5%
131
IOI '94 P4 - The Clocks
IOI
10
27.4%
123
IOI '95 P1 - Packing Rectangles
IOI
15p
44.9%
27
IOI '95 P2 - Shopping Offers
IOI
15p
27.5%
42
IOI '95 P4 - Letter Game
IOI
15p
27.1%
35
IOI '95 P5 - Street Race
IOI
15p
24.5%
40
IOI '95 Practice Task 1 - Fence Factory
IOI
15p
22.9%
11
IOI '95 Practice Task 2 - Word Chains
IOI
12
44.2%
55
IOI '95 Practice Task 3 - Bar Codes
IOI
12p
36.6%
24
IOI '96 P1 - A Game
IOI
10
39.6%
284
IOI '96 P2 - Job Processing
IOI
20p
29.7%
55
IOI '96 P3 - Network of Schools
IOI
12p
24.3%
86
IOI '96 P4 - Sorting a Three-Valued Sequence
IOI
10
31.6%
155
IOI '96 P5 - Longest Prefix
IOI
12
21.1%
114
IOI '97 P1 - Mars Explorer
IOI
20p
12.8%
16
IOI '97 P3 - The Toxic iShongololo
IOI
20p
45.3%
7
IOI '97 P4 - Map Labelling
IOI
20p
56.0%
5
IOI '98 P1 - Contact
IOI
10p
9.3%
60
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