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
...
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
CCC '24 J4 - Troublesome Keys
COCI '22 Contest 4 #1 7Krokods
CCC '24 S2 - Heavy-Light Composition
CCC '19 J3 - Cold Compress
CCC '24 J5 - Harvest Waterloo
COCI '23 Contest 5 #1 Zlagalica
CCC '24 S3 - Swipe
Problem
Category
Points
AC % ▴
Users
WC '15 Contest 2 J4 - The Force Awakens (Junior)
Woburn Challenge
15p
2.3%
11
Mock CCC '23 2 S2 - Keenan Hates Triangles
Mock CCC
7p
2.3%
38
COCI '17 Contest 6 #6 Vrtić
COCI
25p
2.3%
1
IOI '19 P4 - Broken Line
IOI
35p
2.3%
4
Mock CCC '19 Contest 1 S5 - Pusheen Eats Even More Tuna Sashimi and Tuna Nigiri
Mock CCC
20
2.3%
9
TLE 2018-19 P5 - Pure Functional Programming
Seasonal
40p
2.3%
4
Overflow
Uncategorized
30p
2.4%
7
DMOPC '18 Contest 2 P6 - Standing Ovation (Hard Version)
DMOPC
35
2.4%
1
NOI '22 P5 - Bubble Sort
China NOI
35p
2.4%
1
NOI '05 P5 - Little H's Party
China NOI
30p
2.4%
3
Yet Another Contest 3 P3 - Topography
YAC
15p
2.4%
17
Fast Factorial Calculator 3
Uncategorized
40
2.5%
8
Yet Another Contest 5 P4 - Nils++
YAC
17p
2.5%
7
DMOPC '20 Contest 3 P4 - Bob and Typography
DMOPC
15p
2.5%
9
Lyndon's Golf Contest 1 P7 - Fun Factoring
Uncategorized
0p
2.5%
9
IOI '20 P5 - Counting Mushrooms
IOI
35p
2.5%
3
NOI '19 P6 - Explore
China NOI
25p
2.6%
10
NOI '10 P6 - Happily Growing
China NOI
50p
2.6%
2
MMM '14 G - Campfire Cooking
Uncategorized
40p
2.7%
3
IOI '13 P2 - Art Class (Standard I/O)
IOI
20p
2.7%
88
Wesley's Anger Contest 5 Problem 7 - Acorn Delivery System
WAC
30p
2.8%
7
Mock CCC '20 Contest 1 J5 - A Prime Problem
Mock CCC
12p
2.8%
20
NOI '22 Multi-Provincial Team Selection P3 - Community
China NOI
40p
2.9%
1
COI '20 #4 MalnaRISC
COCI
20p
2.9%
8
WC '02 P9 - A Nerd's Preparation
Woburn Challenge
20p
2.9%
3
Ancient Castle Ruins
Uncategorized
25p
2.9%
1
IOI '12 P1 - Pebbling Odometer
IOI
30p
3.0%
4
April Fools' Day Contest 1 P6 - April Fools' Day (BOJ Edition)
Uncategorized
0
3.1%
141
CCO Preparation Test 5 P4 - Toys
Mock CCO
15p
3.1%
2
IOI '22 P6 - Thousands Islands
IOI
30p
3.1%
6
DMOPC '20 Contest 5 P6 - Top Row
DMOPC
35p
3.1%
5
Piggy
Seasonal
7p
3.1%
286
WC '02 Suicidal P5 - The Mines of Moria
Woburn Challenge
25
3.1%
1
IOI '04 P3 - Polygon
IOI
20p
3.1%
1
Mock CCC '24 Contest 1 S3 - Optimal Split Point
Mock CCC
10p
3.1%
21
2048
Uncategorized
15
3.1%
88
An Animal Contest 3 P8 - Monkey Retirement
AAC
25p
3.2%
8
Maximum Product of K Integers
Uncategorized
25
3.2%
2
COCI '10 Contest 6 #6 Voda
COCI
20p
3.2%
1
April Fools' Day Contest 1 P7 - Half-Plane Intersection
Uncategorized
0
3.2%
71
Yet Another Contest 8 P4 - Fluke 2
YAC
15p
3.3%
43
Calendar Contest Problem 5 — Reign of Terror
Uncategorized
15
3.3%
2
NOI '20 P6 - Road
China NOI
45p
3.3%
1
IOI '23 P2 - Longest Trip
IOI
25p
3.3%
12
IOI '15 P3 - Teams (Standard I/O)
IOI
35p
3.4%
36
DMOPC '19 Contest 4 P4 - Math Class
DMOPC
15p
3.4%
16
IOI '11 P6 - Parrots
IOI
20p
3.4%
15
Geometric Sequence
Uncategorized
10
3.4%
8
The Contest Contest 1 P4 - A Typical YAC Problem
Uncategorized
25p
3.4%
7
String Test
Data Structure Tests
50
3.4%
2
«
1
2
3
4
5
6
...
99
100
»