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Hot problems
CCC '25 J3 - Product Codes
CCC '25 J5 - Connecting Territories
CCC '25 J4 - Sunny Days
Problem
Category
Points
AC %
Users
Permutation Sorting
Olympiads School
20p
20.3%
20
Tree Journey
Olympiads School
12p
51.2%
40
Infinity Card Decks
Olympiads School
15p
18.1%
23
City Travel
Olympiads School
15p
17.8%
25
Three Colors
Olympiads School
12p
48.2%
38
Three Nodes
Olympiads School
17p
11.9%
21
0-1 Sequence
Olympiads School
15p
21.7%
7
Olympic Scoring
Uncategorized
3
13.3%
138
Longest Up-Down Subsequence
POI
12p
30.3%
134
A Fenwick Tree Question
Olympiads School
15
30.8%
67
Ones
Uncategorized
7p
13.6%
11
Matchings
POI
30p
15.2%
3
Mailing Origami
Uncategorized
20
9.1%
67
Returning Home
Uncategorized
10
23.1%
80
One Small Favour
Uncategorized
10p
1.1%
17
Another Small Favour
Uncategorized
15p
5.3%
9
OTHS Coding Competition 1 (Mock CCC) J1 - Math Assistance
Uncategorized
3
65.2%
445
OTHS Coding Competition 1 (Mock CCC) J2 - Wand Selection
Uncategorized
3
57.1%
360
OTHS Coding Competition 1 (Mock CCC) J3 - Explosion
Uncategorized
5p
35.5%
259
OTHS Coding Competition 1 (Mock CCC) J4 - Railgun
Uncategorized
7p
23.9%
188
OTHS Coding Competition 1 (Mock CCC) J5 - Scavenger Hunt
Uncategorized
10p
20.6%
84
OTHS Coding Competition 2 P1 - Chess Pieces
Uncategorized
3
56.8%
353
OTHS Coding Competition 2 P2 - Ghoul Investigators
Uncategorized
3p
44.5%
281
OTHS Coding Competition 2 P3 - Tally Clicker
Uncategorized
5
41.6%
256
OTHS Coding Competition 2 P4 - Magic Barrier
Uncategorized
5p
37.2%
199
OTHS Coding Competition 2 P5 - Coffee Jelly
Uncategorized
7
40.2%
166
OTHS Coding Competition 3 (Mock CCC) S1 - The 5th Laboratory
Uncategorized
5
21.5%
142
OTHS Coding Competition 3 (Mock CCC) S2 - Together Forever
Uncategorized
7p
13.8%
73
OTHS Coding Competition 3 (Mock CCC) S3 - Domain Expansion
Uncategorized
10p
29.4%
61
OTHS Coding Competition 3 (Mock CCC) S4 - Magic Library
Uncategorized
15p
12.8%
24
OTHS Coding Competition 3 (Mock CCC) S5 - World Tree
Uncategorized
15p
20.4%
21
BlueBook - Cross Country
BlueBook
3
43.2%
1355
BlueBook - Cost
BlueBook
3
20.9%
749
BlueBook - Direction
BlueBook
3
39.7%
934
BlueBook - Pay
BlueBook
3
19.8%
405
BlueBook - Change
BlueBook
3
9.4%
217
BlueBook - Times Tables
BlueBook
3
54.9%
1551
BlueBook - Max is Last
BlueBook
3
41.3%
532
BlueBook - Interest
BlueBook
3
28.8%
604
BlueBook - World Pop
BlueBook
3
28.8%
518
BlueBook - Power Base
BlueBook
3
40.4%
588
BlueBook - Powers of 2
BlueBook
3
36.2%
715
BlueBook - Find the Character
BlueBook
3
39.3%
614
BlueBook - Column of Numbers
BlueBook
3
42.9%
723
BlueBook - Pop Explosion
BlueBook
3
58.7%
440
BlueBook - Digits and Sums
BlueBook
3
54.2%
467
BlueBook - Exact Divisors
BlueBook
3
63.7%
1027
BlueBook - 10 Primes on a Line
BlueBook
5
26.9%
452
BlueBook - Bills Bills Bills
BlueBook
7
14.3%
159
BlueBook - Max
BlueBook
3
20.2%
461
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