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
»
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
CCC '24 S2 - Heavy-Light Composition
Educational DP Contest AtCoder K - Stones
Educational DP Contest AtCoder I - Coins
IOI '94 P1 - The Triangle
COCI '06 Regional #3 Firefly
CCC '17 J4 - Favourite Times
ICPC PACNW 2016 A - Alphabet
Problem
Category
Points
AC %
Users ▾
CCO '00 P5 - Millikan's Oil Droplet Experiment
CCO
7
22.3%
54
CCO '21 P4 - Travelling Merchant
CCO
25p
19.0%
54
CCO '23 P4 - Flip it and Stick it
CCO
17p
6.8%
53
CCO '10 P5 - Space Miner
CCO
15
31.5%
52
CCO '18 P5 - Boring Lectures (Online Version)
CCO
30p
7.4%
50
CCO '09 P2 - Dinner
CCO
20p
9.8%
50
CCO '21 P3 - Through Another Maze Darkly
CCO
25p
20.5%
49
CCO '01 P6 - Election Night
CCO
15
15.2%
47
CCO '04 P4 - Return of Space Turtle
CCO
12
14.2%
46
CCO '08 P3 - Mobile
CCO
17p
31.3%
46
CCO '09 P5 - Parade
CCO
17p
17.3%
43
CCO '05 P2 - The Great Spamway Strike
CCO
20
40.8%
43
CCO '04 P6 - Orko
CCO
15
31.6%
42
CCO '08 P6 - Landing
CCO
45
20.2%
40
CCO '20 P6 - Shopping Plans
CCO
30p
9.2%
40
CCO '09 P4 - Bottle Caps
CCO
20p
14.3%
38
CCO '02 P4 - Duathlon
CCO
10
11.3%
38
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
CCO '17 P6 - Shifty Grid
CCO
30p
17.8%
34
CCO '09 P3 - Beware the Geoducks
CCO
10
9.8%
34
CCO '22 P5 - Phone Plans
CCO
20p
12.4%
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
CCO '05 P6 - Windows
CCO
30p
14.2%
28
CCO '22 P3 - Double Attendance
CCO
25p
7.4%
28
CCO '20 P3 - Mountains and Valleys
CCO
35p
5.8%
25
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
CCO '98 P2 - Message Deciphering
CCO
7
51.9%
20
CCO '99 P4 - Maple Roundup
CCO
10
21.8%
19
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
7.9%
17
CCO '99 P1 - You Can't Get There From Here
CCO
7
26.5%
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 '21 P6 - Loop Town
CCO
50p
4.7%
13
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
«
1
2
3
4
»