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Hot problems
CCC '20 S4 - Swapping Seats
CCC '24 J4 - Troublesome Keys
Singularity Cup P2 - Reverse Substring Partitioning
CCC '20 J4 - Cyclic Shifts
Singularity Cup P1 - Maximum Permutation Product
Strict Evaluation
CCC '13 S1 - From 1987 to 2013
Problem
Category
Points
AC %
Users
IOI '94 P2 - The Castle
IOI
10
18.3%
130
IOI '94 P4 - The Clocks
IOI
10
27.3%
122
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
21.7%
10
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%
282
IOI '96 P2 - Job Processing
IOI
20p
30.1%
54
IOI '96 P3 - Network of Schools
IOI
12p
24.2%
86
IOI '96 P4 - Sorting a Three-Valued Sequence
IOI
10
32.2%
146
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%
59
IOI '98 P2 - Starry Night
IOI
15
35.1%
30
IOI '98 P3 - Party Lamps
IOI
12p
34.2%
171
IOI '98 P4 - Picture
IOI
15p
31.1%
227
IOI '98 P5 - Camelot
IOI
15p
40.9%
52
IOI '98 P6 - Polygon
IOI
15
32.2%
63
IOI '99 P1 - Little Shop of Flowers
IOI
10
30.7%
216
IOI '99 P2 - Hidden Codes
IOI
20p
14.9%
11
IOI '99 P4 - Traffic Lights
IOI
15
31.4%
30
IOI '99 P5 - Flatten
IOI
15p
21.6%
16
IOI '99 P6 - A Strip of Land
IOI
20p
13.6%
36
IOIQR P5 - Some Game
Seasonal
25
3.5%
3
Jack Needs Help
Uncategorized
10p
32.0%
20
JOI '13 Open P2 - Synchronization
JOI
35p
29.8%
56
JOI '13 Open P3 - Watching
JOI
15p
30.1%
98
JOI '14 Open P1 - Factories
JOI
20p
32.8%
158
JOI '14 Open P2 - Fortune Telling 2
JOI
25p
22.8%
89
JOI '14 Open P3 - Space Pirate
JOI
50p
1.2%
1
JOI '14 Open P5 - Pinball
JOI
25p
26.3%
95
JOI '14 Open P6 - Secret
JOI
17p
16.0%
121
JOI '16 Final P1 - Foehn Phenomena
JOI
10p
60.7%
26
JOI '16 Final P2 - Semiexpress
JOI
12
54.8%
17
JOI '16 Open P2 - Selling RNA Strands
JOI
20
17.4%
20
JOI '16 Open P3 - Skyscraper
JOI
25p
41.6%
51
JOI '17 Final P4 - Commuter Pass
JOI
15
26.8%
61
JOI '17 Final P5 - Snake Escaping
JOI
25p
40.3%
20
JOI '18 Open P1 - Bubble Sort 2
JOI
20p
5.5%
29
JOI '18 Spring Camp Day 1 P1 - Construction of Highway
JOI
30p
34.4%
29
JOI '18 Spring Camp Day 1 P2 - Fences
JOI
30p
25.0%
1
JOI '18 Spring Camp Day 1 P3 - Tents
JOI
20p
63.3%
34
JOI '19 Final P3 - Collecting Stamps 3
JOI
15
25.7%
40
JOI '19 Open P1 - Triple Jump
JOI
30p
24.4%
17
JOI '19 Open P2 - Remittance
JOI
30p
23.6%
13
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