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
6
7
8
9
»
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
APIO '10 P1 - Commando
COCI '08 Contest 3 #6 Najkraci
CCC '24 J5 - Harvest Waterloo
TSS Club Fair 2017 Problem B
CCC '24 J4 - Troublesome Keys
CCC '04 S2 - TopYodeller
DWITE '10 R3 #3 - Dominos Tiling
Problem
Category
Points ▾
AC %
Users
Mock CCC '18 Contest 2 S5 - A Link/Cut Tree Problem
Mock CCC
15p
23.1%
89
CCC '18 S4 - Balanced Trees
CCC
15p
16.9%
576
Mock CCC '19 Contest 2 S5 - Tudor Takes Pictures of Goats
Mock CCC
15
6.8%
14
CCC '20 S2 - Escape Room (Hard)
CCC
15p
5.6%
55
Mock CCC '14 S5 - Elimination Game
Mock CCC
15p
21.8%
56
Mock CCC '14 S4 - Roadtrip Tracking
Mock CCC
15p
9.0%
57
CCCHK '15 S4 - When to meet?
CCC
15p
20.0%
8
CCC '21 S5 - Math Homework
CCC
15p
24.4%
419
Mock CCC '22 2 S4 - Kaguya Wants to Build a Great Wall
Mock CCC
15p
7.5%
8
CCC '22 S4 - Good Triplets
CCC
15p
28.5%
310
Mock CCC '23 1 S4 - Roger Says Yabe
Mock CCC
15p
7.2%
19
Mock CCC '23 2 S4 - Roger Says Yabe
Mock CCC
15p
19.0%
7
CCC '23 S4 - Minimum Cost Roads
CCC
15p
19.6%
256
CCC '05 S5 - Pinball Ranking
CCC
12p
19.5%
741
CCC '06 S3 - Tin Can Telephone
CCC
12
20.8%
528
CCC '09 S5 - Wireless
CCC
12p
34.8%
622
CCC '11 S5 - Switch
CCC
12p
18.3%
415
Mock CCC '15 S3 - The Tachyon Trap
Mock CCC
12p
18.4%
65
CCC '16 S3 - Phonomenal Reviews
CCC
12p
26.4%
1103
CCC '99 S4 - A Knightly Pursuit
CCC
12
18.7%
348
CCC '99 S5 - Letter Arithmetic
CCC
12
16.0%
77
Mock CCC '18 Contest 1 S4 - A Graph Problem
Mock CCC
12p
19.9%
97
Mock CCC '18 Contest 2 S4 - A Tree Problem
Mock CCC
12p
17.9%
65
CCC '18 S3 - RoboThieves
CCC
12p
14.1%
1135
Mock CCC '19 Contest 1 S4 - Pusheen Plays Neko Atsume
Mock CCC
12
17.8%
100
Mock CCC '19 Contest 1 S3 - Pusheen Eats Tuna Sashimi and Tuna Nigiri
Mock CCC
12p
5.2%
54
CCC '19 S3 - Arithmetic Square
CCC
12p
13.6%
501
Mock CCC '20 Contest 1 J5 - A Prime Problem
Mock CCC
12p
2.8%
20
CCC '20 J4 - Cyclic Shifts (Hard)
CCC
12p
3.8%
36
CCC '20 S3 - Searching for Strings
CCC
12p
8.9%
843
CCC '20 S4 - Swapping Seats
CCC
12p
25.6%
491
CCCHK '15 S3 - Symmetric Cross
CCC
12p
16.2%
20
Riolku's Mock CCC S3 - Mosey's Birthday
Mock CCC
12p
11.7%
63
Riolku's Mock CCC S4 - Clumsy Cindy
Mock CCC
12p
10.7%
70
Mock CCC '21 S4 - Infinite Molecule
Mock CCC
12p
8.2%
29
Riolku's Mock CCC S2 - Keen Keener Sequence (Hard Version)
Mock CCC
12
10.7%
17
CCC '21 S4 - Daily Commute
CCC
12p
26.0%
585
Canada Day Contest 2021 - CCC Bad Haha
Seasonal
12
36.1%
249
Mock CCC '22 2 S3 - Kaguya Wants to Analyze the Academy Anthem
Mock CCC
12p
7.9%
40
Mock CCC '23 Contest 1 J5 - Calculus Problem
Mock CCC
12p
10.1%
41
Mock CCC '24 Contest 1 S4 - Tommy's Lemonade Stand
Mock CCC
12p
22.0%
29
CCC '24 S4 - Painting Roads
CCC
12p
35.9%
164
CCC '13 S3 - Chances of Winning
CCC
10
41.2%
1365
CCC '05 J5 - Bananas
CCC
10
21.6%
1469
CCC '06 S4 - Groups
CCC
10
46.5%
328
CCC '04 J5 - Fractals
CCC
10
35.7%
220
CCC '07 S5 - Bowling for Numbers
CCC
10p
29.9%
868
CCC '08 S5 - Nukit
CCC
10p
37.1%
708
CCC '08 S4 - Twenty-four
CCC
10
25.5%
744
CCC '96 S4 - When in Rome
CCC
10
33.0%
569
«
1
2
3
4
5
6
7
8
9
»