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Hot problems
DWITE '10 R3 #3 - Dominos Tiling
APIO '10 P1 - Commando
Counting Subsequences
A Math Contest P5 - Good Arrays
ECOO '13 R1 P1 - Take a Number
An Animal Contest 2 P3 - Koala Balloons
CCC '24 J3 - Bronze Count
Problem
Category
Points
AC % ▾
Users
Mock CCC '18 Contest 2 S4 - A Tree Problem
Mock CCC
12p
17.9%
65
CCC '14 S5 - Lazy Fox
CCC
20p
17.9%
456
Mock CCC '19 Contest 1 S4 - Pusheen Plays Neko Atsume
Mock CCC
12
17.8%
100
CCC '24 S3 - Swipe
CCC
10p
17.6%
173
CCC '03 S5 - Trucking Troubles
CCC
10p
17.6%
684
Mock CCC '18 Contest 2 J4/S2 - A Geometry Problem
Mock CCC
7p
17.5%
122
CCC '00 S3 - Surfing
CCC
7
17.5%
621
Mock CCC '19 Contest 2 J3 - Tudor Buys Some Tea
Mock CCC
3p
17.4%
298
CCC '03 S2 - Poetry
CCC
5
17.3%
1456
Mock CCC '14 J3 - Clock Hands
Mock CCC
5
17.2%
107
TLE '16 Contest 6 (Mock CCC) S3 - Hyper Fax
TLE
15p
17.1%
156
Mock CCC '19 Contest 1 J5 - Pusheen Designs a Sushi Boat
Mock CCC
7p
17.1%
235
Mock CCC '23 Contest 1 J4 - String Decryption
Mock CCC
5p
16.9%
166
CCC '18 S4 - Balanced Trees
CCC
15p
16.9%
576
CCC '13 S4 - Who is Taller?
CCC
7
16.8%
1233
Mock CCC '22 Contest 1 J4 - Snowball Fight
Mock CCC
5p
16.7%
239
Mock CCC '15 J5 - Royal Guard
Mock CCC
10p
16.6%
161
CCC '98 S3 - Mars Rover
CCC
7p
16.5%
161
CCC '99 S3 - Divided Fractals
CCC
7
16.5%
68
CCC '23 S5 - The Filter
CCC
20p
16.3%
88
CCCHK '15 S3 - Symmetric Cross
CCC
12p
16.2%
20
Mock CCC '18 Contest 2 J3/S1 - An Array Problem
Mock CCC
7p
16.1%
372
CCC '99 S5 - Letter Arithmetic
CCC
12
16.0%
77
Mock CCC '22 Contest 2 J5 - Dominating the Olympics
Mock CCC
10
16.0%
76
Mock CCC '14 S2 - Sleep Cycle
Mock CCC
7p
15.9%
103
Mock CCC '20 Contest 2 S3 - Tree Programming
Mock CCC
10p
15.5%
79
Riolku's Mock CCC S2 - Keen Keener Sequence
Mock CCC
7p
15.4%
147
CCC '23 S3 - Palindromic Poster
CCC
10p
15.3%
420
CCC '99 S2 - Year 2000
CCC
7
14.6%
105
The Contest Contest 1 P2 - A Typical CCC Senior Problem
Uncategorized
10p
14.3%
177
TLE '16 Contest 6 (Mock CCC) J3 - Two Kangaroos
TLE
5p
14.2%
42
Mock CCC '24 Contest 1 S5 - Mock CCC 2025
Mock CCC
20p
14.2%
18
CCC '18 S3 - RoboThieves
CCC
12p
14.1%
1135
CCC '17 S4 - Minimum Cost Flow
CCC
17p
14.1%
771
CCC '10 S1 - Computer Purchase
CCC
5
14.1%
1326
Mock CCC '23 1 S5 - The Obligatory Data Structures Problem
Mock CCC
25p
14.0%
10
CCC '02 S5 - Follow the Bouncing Ball
CCC
10
13.8%
190
CCCHK '15 S1 - Finding number of pairs
CCC
7p
13.7%
143
CCC '19 S3 - Arithmetic Square
CCC
12p
13.6%
501
Mock CCC '22 1 S1 - Big Mattress Tournament
Mock CCC
5p
13.4%
206
Mock CCC '24 Contest 1 J3 - RGB Words
Mock CCC
5p
13.3%
187
Mock CCC '23 1 S1 - Composite Fibonacci Numbers
Mock CCC
5p
13.0%
148
CCC '98 S5 - Mountain Passage
CCC
10
13.0%
148
CCC '20 S2 - Escape Room
CCC
10p
12.8%
1695
Mock CCC '20 S3 - SAM I Am
Mock CCC
10p
12.7%
72
Mock CCC '22 Contest 1 J3 - String Crossing Maximization
Mock CCC
7p
12.6%
247
Mock CCC '23 Contest 1 J3 - Pairing Gifts
Mock CCC
5p
12.5%
243
CCC '97 S4 - Dynamic Dictionary Coding
CCC
5
11.8%
221
Mock CCC '20 Contest 2 S4 - Rotational Arrays
Mock CCC
10p
11.8%
61
Riolku's Mock CCC S3 - Mosey's Birthday
Mock CCC
12p
11.7%
63
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