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
...
13
14
15
16
17
18
...
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
Educational DP Contest AtCoder T - Permutation
APIO '09 P3 - The Great ATM Robbery
CCC '24 S2 - Heavy-Light Composition
COCI '11 Contest 5 #2 Eko
ICPC PACNW 2016 A - Alphabet
Appleby Contest '19 P5 - Matrix Operation
Max's Anger Contest Series 2 P3 - Array Anger
Problem
Category
Points
AC % ▾
Users
CCO '97 P5 - Space Aliens
CCO
10
46.7%
3
CCO '98 P6 - Derek's Dilemma
CCO
12
46.7%
4
COCI '17 Contest 7 #4 Clickbait
COCI
15p
46.7%
6
COCI '13 Contest 3 #5 Parovi
COCI
12p
46.7%
16
COCI '11 Contest 5 #1 Križaljka
COCI
3p
46.7%
54
NOI '23 P4 - Trade
China NOI
20p
46.7%
7
IOI '03 Practice Task 1 - Balancing Act
IOI
15
46.6%
125
GlobeX Cup '18 S Sample - Chair Stacking
Uncategorized
7p
46.6%
127
COCI '14 Contest 5 #3 Traktor
COCI
7p
46.6%
278
DWITE '09 R2 #1 - Angles
DWITE
5
46.6%
18
Checkerboard Summation (Hard)
Uncategorized
15p
46.5%
243
CCC '06 S4 - Groups
CCC
10
46.5%
328
COCI '09 Contest 5 #4 Zuma
COCI
15
46.5%
71
ICPC ECNA 2016 C - The Key to Cryptography
ICPC
7
46.4%
61
Waterloo 2017 Fall A - Art
Waterloo Local
3p
46.4%
108
COCI '08 Regional #6 Cvjetici
COCI
12
46.4%
179
NOI '08 P3 - Hiring Employees
China NOI
25p
46.4%
41
Cheerio Contest 1 S5 - Coin Game
Uncategorized
15p
46.4%
35
IOI '09 P5 - Garage
IOI
7
46.4%
532
ECOO '20 P2 - Online Shopping
ECOO
5p
46.4%
370
TSOC '15 Contest 2 #5 - Bebiliths
TSOC
5p
46.4%
209
DWITE '10 R3 #3 - Dominos Tiling
DWITE
10
46.3%
266
Waterloo 2017 Winter D - Vera and Sorting
Waterloo Local
15
46.3%
29
CTU Open Contest 2017 - Punching Power
ICPC
15
46.3%
15
DWITE '11 R5 #4 - Cube World
DWITE
12
46.3%
70
DWITE '09 R5 #4 - Kind of like OCR
DWITE
7
46.3%
18
Tree Paths
Uncategorized
12p
46.3%
9
CCC '19 J3 - Cold Compress
CCC
5
46.2%
3155
CTU Open Contest 2017 - Ice Cream Samples
ICPC
12
46.2%
5
CTU Open Contest 2017 - Go Northwest!
ICPC
7
46.2%
9
COCI '13 Contest 6 #4 Kružnice
COCI
12p
46.2%
14
COI '12 #3 Snjeguljica
COCI
17p
46.2%
21
Google Code Jam '21 Qualification Round Problem B - Moons and Umbrellas
Google Code Jam
7p
46.2%
6
VMSS Pre-Pre-Windsor P2 - Big Chess
Uncategorized
3
46.1%
415
COCI '14 Contest 7 #1 Teta
COCI
5p
46.1%
99
COCI '23 Contest 2 #2 Pingvin
COCI
7p
46.1%
36
DWITE '09 R3 #1 - Quiz Time
DWITE
3
46.1%
97
COCI '08 Contest 2 #1 Kornislav
COCI
5
46.1%
398
COCI '08 Contest 4 #2 Datum
COCI
3
46.0%
323
CCC '19 S1 - Flipper
CCC
3p
46.0%
3954
COCI '20 Contest 3 #2 Vlak
COCI
10p
46.0%
49
Facebook Hacker Cup '15 Round 1 P4 - Corporate Gifting
FHC
17
46.0%
88
ECOO '15 R3 P1 - Just the Factoradics, Ma'am
ECOO
7p
46.0%
35
Lexicographically Least Substring
Uncategorized
5
46.0%
616
COCI '19 Contest 5 #1 Emacs
COCI
5p
46.0%
281
Educational DP Contest AtCoder A - Frog 1
Uncategorized
7
46.0%
1175
DMOPC '14 Exam Time P2 - Physics Duel
DMOPC
5p
46.0%
125
DWITE '08 R5 #3 - Working Directory
DWITE
7
45.9%
16
Baltic OI '15 P2 - Editor
Baltic OI
25p
45.9%
9
CCC '97 S2 - Nasty Numbers
CCC
5
45.9%
794
«
1
2
...
13
14
15
16
17
18
...
99
100
»