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Random
Hot problems
COCI '14 Contest 6 #4 Kratki
CCO '23 P1 - Binaria
ACSL '09 Practice P4 - Rank
Educational DP Contest AtCoder B - Frog 2
CCO '23 P2 - Real Mountains
IOI '00 P1 - Palindrome
CCC '17 S3 - Nailed It!
Problem
Category
Points
AC %
Users ▴
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 '23 P5 - Travelling Trader
CCO
30p
7.9%
17
CCO '98 P5 - Text Segmentation
CCO
10
23.7%
18
CCO '23 P6 - Triangle Collection
CCO
25p
16.7%
18
CCO '99 P4 - Maple Roundup
CCO
10
21.8%
19
CCO Preparation Test 3 P1 - Primitive Pythagorean Pairs
Mock CCO
25p
13.7%
20
CCO '98 P2 - Message Deciphering
CCO
7
51.9%
20
Mock CCO '18 Contest 2 Problem 2 - Victor Rains
Mock CCO
20p
27.7%
21
CCO '97 P1 - Palindromes
CCO
10
11.0%
21
Mock CCO '18 Contest 2 Problem 4 - Victor's Rectangles
Mock CCO
20p
21.9%
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 3 Problem 2 - Roger Delegates Work to Jessica
Mock CCO
20p
28.9%
23
The Contest Contest 1 P5 - A Typical CCO Problem
Uncategorized
20p
4.2%
24
Mock CCO '17 Problem 6 - Dire Consequences
Mock CCO
20
24.2%
25
CCO '20 P3 - Mountains and Valleys
CCO
35p
5.8%
25
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 '96 P6 - Hoppers
CCO
15
15.5%
29
CCO '01 P5 - Fast Food
CCO
7
10.1%
29
CCO '22 P4 - Bi-ing Lottery Treekets
CCO
20p
20.6%
29
CCO '03 P2 - Concentration Cards
CCO
15
36.1%
31
CCO Preparation Test 2 P1 - Concatenation
Mock CCO
17p
13.1%
32
CCO '22 P5 - Phone Plans
CCO
20p
12.9%
32
Mock CCO '18 Contest 3 Problem 3 - Roger Just Plays Some More Chess
Mock CCO
20p
12.3%
33
CCO '17 P6 - Shifty Grid
CCO
30p
17.8%
34
CCO '09 P3 - Beware the Geoducks
CCO
10
9.8%
34
Mock CCO '18 Contest 4 Problem 5 - Spawn More Overlords
Mock CCO
20p
24.8%
35
CCO '02 P2 - Game Show Math
CCO
12
21.4%
35
CCO '06 P2 - R & J
CCO
10
20.8%
35
CCO '01 P4 - Breaking Level (Standard I/O)
CCO
12
7.8%
35
Mock CCO '18 Contest 4 Problem 6 - Splitting Drones
Mock CCO
15p
34.6%
37
CCO '09 P4 - Bottle Caps
CCO
20p
14.2%
37
Mock CCO '17 Problem 3 - Connection
Mock CCO
20p
12.5%
38
Mock CCO '18 Contest 4 Problem 2 - Sunken Colonies
Mock CCO
15p
43.5%
38
CCO '02 P4 - Duathlon
CCO
10
11.3%
38
CCO Preparation Test 1 P2 - Escape Maze
Mock CCO
20p
12.0%
39
CCO Preparation Test 2 P3 - Subsets
Mock CCO
20p
16.7%
39
CCO '08 P6 - Landing
CCO
45
20.2%
40
Mock CCO '18 Contest 4 Problem 1 - Mining for Minerals
Mock CCO
15p
14.2%
40
CCO '20 P6 - Shopping Plans
CCO
30p
9.2%
40
CCO '04 P6 - Orko
CCO
15
31.6%
42
CCO '09 P5 - Parade
CCO
17p
17.3%
43
CCO '05 P2 - The Great Spamway Strike
CCO
20
40.8%
43
Mock CCO '18 Contest 2 Problem 1 - Victor Runs
Mock CCO
15p
16.5%
44
CCO '04 P4 - Return of Space Turtle
CCO
12
14.2%
46
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