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
...
40
41
42
43
44
45
...
99
100
»
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
WC '17 Contest 3 J3 - Uncrackable
Knapsack 4
DMOPC '19 Contest 5 P1 - Conspicuous Cryptic Checklist
CCC '24 S2 - Heavy-Light Composition
DMOPC '18 Contest 1 P2 - Sorting
IOI '07 P4 - Miners
CCCHK '15 J3 - Queens can't attack me!
Problem
Category
Points
AC % ▾
Users
WOSS Dual Olympiad 2022 Team Round P3: Bobby and the Sidewalk
Seasonal
10p
28.9%
39
WC '17 Contest 3 J3 - Uncrackable
Woburn Challenge
5
28.9%
2353
Mock CCO '18 Contest 3 Problem 2 - Roger Delegates Work to Jessica
Mock CCO
20p
28.9%
23
CCC '01 S5 - Post's Correspondence Problem
CCC
10
28.9%
315
COCI '15 Contest 6 #3 Pianino
COCI
10
28.9%
18
UCC Coding Competition '21 P4 - Trampoline Jump
Uncategorized
7p
28.9%
137
QCC P1 - Quarantine Games
Uncategorized
10
28.9%
37
Waterloo 2001 Fall 1 C - Babelfish
Waterloo Local
5
28.9%
12
DMOPC '21 Contest 1 P1 - Partial Game
DMOPC
5p
28.9%
413
NOIP '21 P2 - Sequence
China NOI
20p
28.8%
60
Educational DP Contest AtCoder V - Subtree
Uncategorized
20
28.8%
95
NOI '10 P1 - Energy Harvesting
China NOI
17p
28.8%
68
HCI '16 - Unexpected Factorial
Uncategorized
5p
28.8%
85
Waterloo 2017 Fall C - Computer Science
Waterloo Local
10p
28.8%
26
HCI '16 - Totient
Uncategorized
12p
28.8%
18
COCI '14 Contest 2 #2 Utrka
COCI
5p
28.8%
742
UTS Open '18 P4 - Ianine's Lil Lab
Uncategorized
10p
28.8%
87
COCI '17 Contest 4 #1 Rasvjeta
COCI
3p
28.8%
49
COCI '23 Contest 5 #4 Rolete
COCI
15p
28.8%
17
IOI '09 P3 - POI
IOI
7
28.8%
527
Binary Indexed Tree Test
Data Structure Tests
10p
28.8%
738
Wesley's Anger Contest 3 Problem 2 - Eat, Sleep, Code, Repeat
WAC
5p
28.8%
197
Balkan OI '11 P4 - Compare
Balkan OI
25p
28.8%
17
JOI '13 Open P2 - Synchronization
JOI
35p
28.8%
50
DMOPC '17 Contest 4 P5 - Revised IOI
DMOPC
12
28.8%
38
Another Contest 2 Problem 2 - Poutine
ACC
10
28.8%
138
ICPC NEERC 2010 K - Graph Oddity
ICPC
12p
28.8%
19
Breaking the Friend Chain
Uncategorized
7
28.7%
183
CCC '16 S4 - Combining Riceballs
CCC
15p
28.7%
930
Max's Anger Contest Series 1 P4 - Greedily Gamboling (Hard Version)
Seasonal
15p
28.7%
13
ECOO '21 P1 - Many Messages
ECOO
3p
28.7%
443
COCI '19 Contest 2 #3 Checker
COCI
12p
28.7%
26
VM7WC '15 #1 Gold - JHK
VM7WC
10
28.7%
127
ECOO '16 R1 P4 - Kayenne
ECOO
7p
28.7%
41
DMOPC '17 Contest 2 P1 - 0-1 Knapsack
DMOPC
3
28.7%
359
Lemon Game
Olympiads School
7
28.6%
43
MCIPC Contest 2 P3 - Snowy Streets
Uncategorized
5p
28.6%
46
PEG Test '11 - Cyclopian Cash
Uncategorized
3
28.6%
279
COCI '16 Contest 4 #3 Kas
COCI
10p
28.6%
71
Triple Fat Ladies
Uncategorized
5
28.6%
1558
A Greedy Problem
Uncategorized
5p
28.6%
170
CCC '03 J1 - Trident
CCC
3
28.6%
2316
ICPC ECNA 2000 C - Rational Approximation
ICPC
17
28.6%
2
Triway Cup '18 Summer G - Gu of Love
Seasonal
20
28.6%
6
CCO '99 P3 - Manelzuma's Revenge
CCO
10
28.6%
2
ICPC SWERC 2017 C - Macarons
ICPC
17
28.6%
2
COCI '13 Contest 4 #3 Sumo
COCI
10p
28.6%
34
BPC 1 J5 - Set
Uncategorized
10
28.6%
21
BlueBook - Interest
BlueBook
3
28.6%
573
Rotations in 3 Dimensions
Uncategorized
12
28.5%
117
«
1
2
...
40
41
42
43
44
45
...
99
100
»