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Hot problems
CCC '24 S2 - Heavy-Light Composition
SAC '22 Code Challenge 5 P2 - Querying Extensions
Max's Anger Contest Series 2 P2 - Password Anger
Max's Anger Contest Series 2 P3 - Array Anger
CCC '12 S2 - Aromatic Numbers
The Cosmic Era P2 - Uneven Sand
CCC '20 J4 - Cyclic Shifts
Problem
Category
Points
AC %
Users ▾
Mock CCO '18 Contest 3 Problem 3 - Roger Just Plays Some More Chess
Mock CCO
20p
12.3%
33
CCO '22 P5 - Phone Plans
CCO
20p
12.8%
33
CCO Preparation Test 2 P1 - Concatenation
Mock CCO
17p
13.1%
32
CCO '03 P2 - Concentration Cards
CCO
15
36.1%
31
CCO '22 P4 - Bi-ing Lottery Treekets
CCO
20p
20.5%
30
CCO '96 P6 - Hoppers
CCO
15
15.5%
29
CCO '01 P5 - Fast Food
CCO
7
10.1%
29
Mock CCO '19 Contest 2 Problem 6 - A Fundraising Problem
Mock CCO
12p
15.8%
28
CCO '05 P6 - Windows
CCO
30p
14.2%
28
CCO '22 P3 - Double Attendance
CCO
25p
7.4%
28
CCO '99 P4 - Maple Roundup
CCO
10
20.8%
27
Mock CCO '17 Problem 6 - Dire Consequences
Mock CCO
20
24.2%
25
CCO '20 P3 - Mountains and Valleys
CCO
35p
5.8%
25
The Contest Contest 1 P5 - A Typical CCO Problem
Uncategorized
20p
4.2%
24
Mock CCO '18 Contest 3 Problem 2 - Roger Delegates Work to Jessica
Mock CCO
20p
28.9%
23
Mock CCO '18 Contest 2 Problem 4 - Victor's Rectangles
Mock CCO
20p
21.9%
22
CCO '97 P1 - Palindromes
CCO
10
11.0%
22
CCO '09 P1 - Invasion of the Boxes
CCO
20p
12.8%
22
CCO '02 P1 - Spam
CCO
12
49.1%
22
CCO '23 P3 - Line Town
CCO
30p
9.9%
22
Mock CCO '18 Contest 2 Problem 2 - Victor Rains
Mock CCO
20p
27.7%
21
CCO '98 P2 - Message Deciphering
CCO
7
53.7%
21
CCO Preparation Test 3 P1 - Primitive Pythagorean Pairs
Mock CCO
25p
13.7%
20
CCO '98 P5 - Text Segmentation
CCO
10
23.7%
18
CCO '23 P6 - Triangle Collection
CCO
25p
16.7%
18
CCO '23 P5 - Travelling Trader
CCO
30p
7.6%
17
CCO Preparation Test 7 P2 - XOR Path
Mock CCO
20p
13.5%
16
CCO '99 P1 - You Can't Get There From Here
CCO
7
26.5%
16
Mock CCO '19 Contest 1 Problem 6 - A Geometry Problem
Mock CCO
15p
27.2%
16
CCO '02 P3 - Return To Blind Man's Bluff
CCO
12
12.2%
16
CCO '03 P3 - Cube
CCO
20p
12.4%
14
CCO '14 P6 - Gates
CCO
40p
9.0%
13
CCO Preparation Test 5 P2 - Corporative Network
Mock CCO
15
7.3%
13
Mock CCO '17 Problem 5 - Blitzkrieg
Mock CCO
17p
12.4%
13
Mock CCO '19 Contest 1 Problem 4 - A Chemistry Problem
Mock CCO
15p
14.9%
13
CCO '21 P6 - Loop Town
CCO
50p
4.7%
13
Mock CCO '18 Contest 3 Problem 1 - Roger Meets For DMPG
Mock CCO
15p
9.6%
12
CCO '22 P6 - Good Game
CCO
35p
19.6%
12
CCO '97 P6 - Aligning DNA
CCO
7
19.1%
11
CCO '00 P3 - The Game Of 31
CCO
15
54.5%
11
CCO '01 P2 - Coke or Chocolate Milk
CCO
12
17.1%
11
CCO '06 P4 - CN Tower 2
CCO
30
5.4%
11
CCO '07 P5 - Particle Catcher
CCO
30p
16.3%
10
CCO Preparation Test 1 P1 - Double Cross
Mock CCO
20p
12.1%
10
CCO '99 P6 - Fast Food
CCO
15
34.4%
10
CCO Preparation Test 5 P3 - Minimum Cycle
Mock CCO
15p
9.4%
9
Mock CCO '18 Contest 1 Problem 5 - A Counting Problem
Mock CCO
20p
24.5%
9
Mock CCO '18 Contest 2 Problem 6 - Victor's Cubes
Mock CCO
20p
18.3%
9
CCO '02 P6 - Pit Stop Strategy
CCO
12
52.7%
9
CCO '06 P6 - Paint by Numbers
CCO
30
11.0%
9
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