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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
Google Code Jam '18 Qualification Round Problem A - Saving The Universe Again
Google Code Jam
5p
58.3%
6
COCI '08 Contest 3 #2 Kemija
COCI
5
58.3%
1375
COCI '07 Contest 4 #1 Vauvau
COCI
5
58.2%
328
DWITE '07 R3 #1 - Yet Another Primes Question
DWITE
5
58.2%
156
BlueBook - Pop Explosion
BlueBook
3
58.2%
417
Educational DP Contest AtCoder O - Matching
Uncategorized
12
58.2%
324
WC '18 Contest 2 J3 - Seeing Double
Woburn Challenge
3p
58.2%
114
COCI '16 Contest 1 #6 Vještica
COCI
15p
58.1%
21
DWITE '07 R2 #1 - Not Quite Prime
DWITE
5
58.1%
318
DWITE '09 R6 #4 - Time for Change
DWITE
7
58.1%
207
There's a Hole in the Bucket
Uncategorized
7
58.1%
131
COCI '06 Contest 4 #3 Prsteni
COCI
5
58.0%
224
CTU Open Contest 2018 - Numbers Generator
ICPC
20
57.9%
3
IOI '14 Practice Task 2 - Station
IOI
7p
57.9%
50
Balkan OI '11 P2 - Decrypt
Balkan OI
15p
57.9%
9
WC '17 Contest 4 J3 - The Infinity Stones
Woburn Challenge
3p
57.9%
172
CCC '04 J3 - Smile with Similes
CCC
3
57.9%
3937
Educational DP Contest AtCoder T - Permutation
Uncategorized
15
57.8%
111
COCI '22 Contest 4 #3 Bojanje
COCI
17p
57.8%
23
Amplitude Hackathon '23 Practice Problem 1 - Gigatron EPS Modulo 998244353
Uncategorized
3p
57.8%
39
DMOPC '18 Contest 2 P1 - Pumpkin Patches
DMOPC
3
57.7%
435
WC '18 Contest 3 J1 - An Honest Day's Work
Woburn Challenge
3p
57.6%
3078
Summer Institute '17 Contest 1 P9 - Safe Square
SIUCF
7
57.5%
138
NOI '98 P1 - Personal Income Tax
China NOI
7
57.5%
20
IOI '94 P1 - The Triangle
IOI
7p
57.3%
1432
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
COCI '09 Contest 5 #2 Cudoviste
COCI
5
57.3%
107
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
WC '18 Contest 1 J1 - Homework
Woburn Challenge
3p
57.2%
250
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
COCI '08 Contest 3 #1 Pet
COCI
5
57.1%
627
BSSPC '21 J3 - Magic Paint Gun Cartridges
Uncategorized
5
57.1%
148
DMOPC '15 Contest 2 P2 - Admin War
DMOPC
3p
57.0%
483
Hailstone Numbers
Uncategorized
3
57.0%
801
DWITE '09 R1 #2 - Word Scrambler
DWITE
5
57.0%
222
COCI '09 Contest 3 #1 Filip
COCI
3
56.9%
392
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
COCI '06 Contest 3 #3 Trojke
COCI
7
56.6%
142
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