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
...
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
EGOI '21 P1 - Zeros
Educational DP Contest AtCoder M - Candies
CCC '15 J5 - π-day
IOI '14 Practice Task 2 - Station
CCC '00 S4 - Golf
CCC '12 S5 - Mouse Journey
COCI '10 Contest 6 #2 Uspon
Problem
Category
Points
AC % ▾
Users
COCI '19 Contest 5 #5 Zapina
COCI
10p
58.3%
91
Google Code Jam '15 Qualification Round Problem A - Standing Ovation
Google Code Jam
3p
58.3%
9
Google Code Jam '18 Qualification Round Problem A - Saving The Universe Again
Google Code Jam
5p
58.3%
6
DWITE '07 R3 #1 - Yet Another Primes Question
DWITE
5
58.2%
156
BlueBook - Pop Explosion
BlueBook
3
58.2%
417
COCI '06 Contest 6 #2 Magija
COCI
5p
58.2%
133
COCI '08 Contest 3 #2 Kemija
COCI
5
58.2%
1367
COCI '16 Contest 1 #6 Vještica
COCI
15p
58.1%
21
Educational DP Contest AtCoder O - Matching
Uncategorized
12
58.1%
322
DWITE '07 R2 #1 - Not Quite Prime
DWITE
5
58.1%
317
COCI '06 Contest 4 #3 Prsteni
COCI
5
58.0%
224
CCC '04 J3 - Smile with Similes
CCC
3
58.0%
3932
DWITE '09 R6 #4 - Time for Change
DWITE
7
58.0%
202
There's a Hole in the Bucket
Uncategorized
7
57.9%
130
CTU Open Contest 2018 - Numbers Generator
ICPC
20
57.9%
3
Balkan OI '11 P2 - Decrypt
Balkan OI
15p
57.9%
9
Educational DP Contest AtCoder T - Permutation
Uncategorized
15
57.8%
111
WC '18 Contest 2 J3 - Seeing Double
Woburn Challenge
3p
57.8%
112
COCI '22 Contest 4 #3 Bojanje
COCI
17p
57.8%
23
WC '17 Contest 4 J3 - The Infinity Stones
Woburn Challenge
3p
57.7%
171
WC '18 Contest 3 J1 - An Honest Day's Work
Woburn Challenge
3p
57.7%
3063
DMOPC '18 Contest 2 P1 - Pumpkin Patches
DMOPC
3
57.7%
435
Summer Institute '17 Contest 1 P9 - Safe Square
SIUCF
7
57.5%
138
IOI '14 Practice Task 2 - Station
IOI
7p
57.5%
49
NOI '98 P1 - Personal Income Tax
China NOI
7
57.5%
20
BSSPC '21 J3 - Magic Paint Gun Cartridges
Uncategorized
5
57.4%
148
WC '18 Contest 2 S1 - Laser Grid
Woburn Challenge
7p
57.3%
113
Max's Anger Contest Series 2 P1 - Directed Anger
Seasonal
3
57.3%
177
IOI '94 P1 - The Triangle
IOI
7p
57.3%
1429
DMOPC '15 Contest 2 P2 - Admin War
DMOPC
3p
57.3%
482
COCI '09 Contest 5 #2 Cudoviste
COCI
5
57.3%
107
COCI '08 Contest 3 #1 Pet
COCI
5
57.2%
624
Lyndon's Golf Contest 1 P3 - Boolean (Buffed)
Uncategorized
0p
57.2%
79
VM7WC '16 #5 Bronze - Jayden Watches Videos
VM7WC
3
57.2%
225
DWITE '07 R4 #5 - It all adds up
DWITE
7
57.1%
12
Google Code Jam '22 Qualification Round Problem D - Chain Reactions
Google Code Jam
10p
57.1%
7
Google Code Jam '11 Qualification Round Problem A - Bot Trust
Google Code Jam
5
57.1%
3
Google Code Jam '11 Qualification Round Problem B - Candy Splitting
Google Code Jam
7p
57.1%
4
Google Code Jam '14 Qualification Round Problem B - Cookie Clicker Alpha
Google Code Jam
5p
57.1%
3
Waterloo 2003 Spring B - Persistent Numbers
Waterloo Local
5
57.1%
4
WC '18 Contest 1 J1 - Homework
Woburn Challenge
3p
57.1%
249
DWITE '09 R1 #2 - Word Scrambler
DWITE
5
57.0%
222
Hailstone Numbers
Uncategorized
3
57.0%
799
COCI '09 Contest 3 #1 Filip
COCI
3
56.9%
391
CPC '19 Contest 1 P0 - Shoes
Uncategorized
3p
56.8%
262
GFSSOC '15 Fall J3 - Equation Solver
GFSSOC
5p
56.8%
380
HCI '16 - Poké Problem
Uncategorized
7
56.8%
17
DWITE '09 R4 #5 - Ice Maze
DWITE
10
56.7%
33
WOSS Dual Olympiad 2022 J1: Holiday Gifting
Seasonal
3
56.6%
244
DWITE '08 R5 #1 - Baby Diff
DWITE
3
56.6%
146
«
1
2
3
4
5
6
7
8
...
99
100
»