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Random
Hot problems
COCI '14 Contest 5 #3 Traktor
Knapsack 4
IOI '04 P4 - Phidias
WC '17 Contest 3 J3 - Uncrackable
CCCHK '15 J3 - Queens can't attack me!
IOI '07 P4 - Miners
IOI '94 P1 - The Triangle
Problem ▴
Category
Points
AC %
Users
CCO '96 P6 - Hoppers
CCO
15
15.5%
29
CCO '97 P1 - Palindromes
CCO
10
11.1%
21
CCO '97 P2 - Alien Invasion
CCO
10
43.4%
54
CCO '97 P3 - Porous Stone
CCO
10
33.3%
2
CCO '97 P4 - High Tide
CCO
10
11.8%
3
CCO '97 P5 - Space Aliens
CCO
10
46.7%
3
CCO '97 P6 - Aligning DNA
CCO
7
19.1%
11
CCO '98 P1 - Fibonacci Numbers
CCO
7
26.2%
158
CCO '98 P2 - Message Deciphering
CCO
7
51.9%
20
CCO '98 P3 - Bus Schedule
CCO
12
12.5%
2
CCO '98 P4 - Scoring Curling
CCO
7p
25.0%
8
CCO '98 P5 - Text Segmentation
CCO
10
23.7%
18
CCO '98 P6 - Derek's Dilemma
CCO
12
46.7%
4
CCO '99 P1 - You Can't Get There From Here
CCO
7
27.5%
16
CCO '99 P2 - Common Words
CCO
10
12.3%
313
CCO '99 P3 - Manelzuma's Revenge
CCO
10
28.6%
2
CCO '99 P4 - Maple Roundup
CCO
10
21.8%
19
CCO '99 P5 - Sum Of Products
CCO
15
4.3%
1
CCO '99 P6 - Fast Food
CCO
15
34.4%
10
CCO Preparation Test 1 P1 - Double Cross
Mock CCO
20p
12.1%
10
CCO Preparation Test 1 P2 - Escape Maze
Mock CCO
20p
12.0%
39
CCO Preparation Test 1 P3 - K-th Rank Student
Mock CCO
17p
35.2%
151
CCO Preparation Test 2 P1 - Concatenation
Mock CCO
17p
13.1%
32
CCO Preparation Test 2 P2 - Forest Area
Mock CCO
25p
3.8%
5
CCO Preparation Test 2 P3 - Subsets
Mock CCO
20p
16.7%
39
CCO Preparation Test 3 P1 - Primitive Pythagorean Pairs
Mock CCO
25p
13.7%
20
CCO Preparation Test 3 P2 - Packing Up
Mock CCO
25p
14.9%
117
CCO Preparation Test 3 P3 - Arrow
Mock CCO
30p
18.1%
58
CCO Preparation Test 4 P3 - Dynamic MST
Mock CCO
25p
22.4%
49
CCO Preparation Test 5 P1 - City Game
Mock CCO
15
26.4%
202
CCO Preparation Test 5 P2 - Corporative Network
Mock CCO
15
7.3%
13
CCO Preparation Test 5 P3 - Minimum Cycle
Mock CCO
15p
9.4%
9
CCO Preparation Test 5 P4 - Toys
Mock CCO
15p
3.1%
2
CCO Preparation Test 6 P1 - Bus Routes
Mock CCO
20p
24.2%
6
CCO Preparation Test 6 P2 - An Easy Problem
Mock CCO
12p
32.5%
204
CCO Preparation Test 6 P3 - HopScotch
Mock CCO
20p
23.1%
140
CCO Preparation Test 7 P1 - Game of Stone
Mock CCO
20p
6.4%
3
CCO Preparation Test 7 P2 - XOR Path
Mock CCO
20p
13.5%
16
CCOQR '16 - Data Structure
CCC
15p
22.0%
176
CCOQR '16 - Stupendous Bowties
CCC
10p
31.8%
242
CCOQR '16 - Through A Maze Darkly
CCC
20p
18.3%
103
DMPG '16 B3 - CCO
DMOPC
5
41.8%
102
Mock CCO '17 Problem 1 - Fast Fuhrer Transform
Mock CCO
10p
25.4%
60
Mock CCO '17 Problem 2 - Penetrating Power
Mock CCO
17p
25.6%
170
Mock CCO '17 Problem 3 - Connection
Mock CCO
20p
12.5%
38
Mock CCO '17 Problem 4 - Guards
Mock CCO
15p
17.2%
52
Mock CCO '17 Problem 5 - Blitzkrieg
Mock CCO
17p
12.4%
13
Mock CCO '17 Problem 6 - Dire Consequences
Mock CCO
20
24.2%
25
Mock CCO '18 Contest 1 Problem 4 - A Rectangle Problem
Mock CCO
25p
17.4%
7
Mock CCO '18 Contest 1 Problem 5 - A Counting Problem
Mock CCO
20p
24.5%
9
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