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Hot problems
IOI '94 P1 - The Triangle
IOI '14 P3 - Game
CCC '24 J4 - Troublesome Keys
CCC '24 S4 - Painting Roads
CCC '24 J3 - Bronze Count
COCI '22 Contest 1 #5 Neboderi
CCC '11 S1 - English or French?
Problem
Category
Points
AC %
Users ▾
CCC '97 S2 - Nasty Numbers
CCC
5
45.9%
793
Bubble Sort
Uncategorized
7
33.9%
786
Maximum Sum
Uncategorized
7
33.3%
780
DMOPC '14 Contest 2 P1 - Logging Log
DMOPC
3p
37.6%
779
Back From Summer '17 P1: Pithy Pastimes
Seasonal
3
39.2%
779
Fibonacci Sequence
Uncategorized
15p
13.0%
776
ECOO '17 R3 P1 - Baker Brie
ECOO
5p
40.3%
776
CCC '17 S4 - Minimum Cost Flow
CCC
17p
14.1%
769
Mock CCC '15 J1 - 416
Mock CCC
3p
24.1%
760
A Noisy Class
Uncategorized
7
29.4%
751
DMOPC '14 Contest 5 P2 - Longest Tunnel
DMOPC
3p
65.1%
749
Mock CCC '19 Contest 2 J1 - Tudor Drinks Some Tea
Mock CCC
3p
51.9%
748
COCI '17 Contest 1 #1 Cezar
COCI
3
32.7%
744
COCI '14 Contest 2 #2 Utrka
COCI
5p
28.8%
742
Binary Indexed Tree Test
Data Structure Tests
10p
28.8%
738
CCC '05 S5 - Pinball Ranking
CCC
12p
19.5%
737
ECOO '19 R2 P1 - Email
ECOO
5p
31.5%
737
CCC '08 S4 - Twenty-four
CCC
10
25.5%
732
CCC '13 S5 - Factor Solitaire
CCC
15p
42.8%
731
Mock CCC '23 Contest 1 J1 - Final Velocity
Mock CCC
3
67.2%
730
Coin Change
Uncategorized
7
40.4%
725
Is it a Tree?
Seasonal
7p
32.9%
724
DMOPC '14 Contest 7 P2 - Tides
DMOPC
5p
19.1%
724
Word Scrambler
Uncategorized
5
49.7%
721
CCC '04 S2 - TopYodeller
CCC
5
21.5%
721
DMOPC '19 Contest 5 P1 - Conspicuous Cryptic Checklist
DMOPC
5
62.2%
721
CCC '02 J1 - 0123456789
CCC
3
5.3%
718
Mock CCC '19 Contest 1 J2 - Pusheen OCR
Mock CCC
3p
54.7%
714
CCC '08 S5 - Nukit
CCC
10p
37.2%
705
DMPG '16 B1 - BFS
DMOPC
3p
56.3%
704
IOI '01 P1 - Mobile Phones
IOI
15p
27.4%
701
BlueBook - Min
BlueBook
3
39.6%
700
Mock CCC '22 Contest 2 J1 - Opening Ceremony
Mock CCC
3
48.5%
695
BlueBook - Cost
BlueBook
3
20.5%
689
BlueBook - Column of Numbers
BlueBook
3
42.5%
689
CCC '09 J4 - Signage
CCC
7
29.3%
682
Postfix Notation
Uncategorized
7
19.0%
681
BlueBook - Powers of 2
BlueBook
3
36.5%
681
CCC '03 S5 - Trucking Troubles
CCC
10p
17.5%
679
ACM U of T Tryouts C0 B - Interleaving Leaves
ICPC
5
53.9%
679
DMOPC '15 Contest 1 P1 - Itami and Manga
DMOPC
3p
48.6%
678
The Mirror
Uncategorized
5
33.3%
675
CCC '14 S4 - Tinted Glass Window
CCC
15p
29.2%
672
Quine
Classics
10
35.6%
664
Valentine's Day '15 P2 - Simon and Marcy
Seasonal
7p
53.9%
663
COCI '06 Contest 1 #2 Herman
COCI
5
42.1%
654
DMPG '17 S2 - Anime Conventions
DMOPC
7p
27.3%
654
DMOPC '14 Contest 1 P1 - Median Mark
DMOPC
5p
20.3%
652
Mock CCC '22 Contest 1 J1 - Square Root Decomposition
Mock CCC
3
41.4%
652
CCC '22 S3 - Good Samples
CCC
10p
18.3%
651
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