Home
Problems
Submissions
Users
Contests
About
>
Status
Tips
API
Github
Log in
or
Sign up
This site works best with JavaScript enabled.
Problems
«
1
2
3
4
5
»
Problem search
Full text search
Has editorial
Show problem types
Category
All
---
AAC
ACC
APIO
Balkan OI
Baltic OI
BlueBook
Brazil OI
Bubble Cup
Bulgarian OI
CCC
CCO
CEOI
China NOI
Classics
COCI
CSPC
CTF
Data Structure Tests
DMOPC
DWITE
ECOO
EGOI
ESOI
FHC
Fun Math
GFSSOC
Google Code Jam
Google Hash Code
Google Kick Start
ICPC
IOI
JOI
Mock CCC
Mock CCO
MWC
Olympiads School
POI
SAC Coding Challenge
Seasonal
SIUCF
Taiwan NOI
TLE
TSOC
Uncategorized
VM7WC
WAC
Waterloo Local
Woburn Challenge
YAC
Point range
Go
Random
Hot problems
A Game
NOI '15 P2 - Software Package Manager
Knapsack 4
CCC '00 S1 - Slot Machines
DMOPC '21 Contest 7 P1 - Chika Grids
ECOO '17 R3 P1 - Baker Brie
DMOPC '14 Contest 4 P3 - Golden Lily
Problem
Category
Points ▾
AC %
Users
CCO '21 P6 - Loop Town
CCO
50p
4.7%
13
CCO '08 P6 - Landing
CCO
45
20.2%
40
CCO '11 P5 - Fixing Disks
CCO
40p
7.7%
6
CCO '14 P6 - Gates
CCO
40p
9.0%
13
CCO '20 P3 - Mountains and Valleys
CCO
35p
5.8%
25
CCO '22 P6 - Good Game
CCO
35p
19.6%
12
CCO '07 P5 - Particle Catcher
CCO
30p
16.3%
10
CCO Preparation Test 3 P3 - Arrow
Mock CCO
30p
18.1%
58
CCO '15 P6 - Eggscavation
CCO
30p
18.5%
70
CCO '16 P3 - Legends
CCO
30p
9.8%
61
CCO '17 P3 - Vera and Modern Art
CCO
30p
14.1%
93
CCO '17 P6 - Shifty Grid
CCO
30p
17.8%
34
Mock CCO '18 Contest 3 Problem 6 - Roger Asks For More Marks
Mock CCO
30p
15.5%
8
CCO '18 P3 - Fun Palace
CCO
30p
18.1%
76
CCO '18 P6 - Flop Sorting
CCO
30p
17.5%
59
CCO '18 P5 - Boring Lectures (Online Version)
CCO
30p
7.4%
50
CCO '19 P3 - Winter Driving
CCO
30p
17.1%
65
CCO '20 P6 - Shopping Plans
CCO
30p
9.2%
40
CCO '06 P4 - CN Tower 2
CCO
30
5.4%
11
CCO '06 P5 - Domino
CCO
30
3.9%
3
CCO '06 P6 - Paint by Numbers
CCO
30
11.0%
9
CCO '05 P6 - Windows
CCO
30p
14.2%
28
CCO '23 P3 - Line Town
CCO
30p
10.2%
21
CCO '23 P5 - Travelling Trader
CCO
30p
7.9%
17
CCO '13 P6 - Repetitivity
CCO
25p
42.0%
197
CCO Preparation Test 2 P2 - Forest Area
Mock CCO
25p
3.8%
5
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 4 P3 - Dynamic MST
Mock CCO
25p
22.4%
49
CCO '16 P6 - Pirates
CCO
25p
20.7%
70
Mock CCO '18 Contest 1 Problem 4 - A Rectangle Problem
Mock CCO
25p
17.4%
7
Mock CCO '19 Contest 1 Problem 5 - A Tree Problem
Mock CCO
25p
14.3%
6
CCO '19 P4 - Card Scoring
CCO
25p
15.3%
68
CCO '20 P4 - Travelling Salesperson
CCO
25p
19.6%
92
CCO '20 P5 - Interval Collection
CCO
25p
16.0%
60
CCO '06 P3 - Codec
CCO
25p
0.0%
0
CCO '21 P3 - Through Another Maze Darkly
CCO
25p
20.5%
49
CCO '21 P4 - Travelling Merchant
CCO
25p
19.0%
53
CCO '22 P3 - Double Attendance
CCO
25p
7.6%
28
CCO '23 P6 - Triangle Collection
CCO
25p
16.7%
18
CCO '07 P3 - Bowling for Numbers++
CCO
20p
10.5%
80
CCO '07 P4 - Gerrymandering
CCO
20p
1.7%
3
CCO '07 P6 - Road Construction
CCO
20p
30.3%
180
CCO '12 P3 - Mhocskian Languages
CCO
20p
49.6%
103
CCO '13 P4 - A Romantic Movie Outing
CCO
20p
23.5%
91
CCO '14 P5 - Early Exam Evacuation
CCO
20p
23.3%
87
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 2 P3 - Subsets
Mock CCO
20p
16.7%
39
CCO '15 P3 - Solar Flight
CCO
20p
12.8%
68
«
1
2
3
4
5
»