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Problem Category Points AC % ▴ Users
CCC '20 S2 - Escape Room CCC 10p 12.8% 1690
CCO '09 P1 - Invasion of the Boxes CCO 20p 12.8% 22
IOI '97 P1 - Mars Explorer IOI 20p 12.8% 16
New Year's '17 P3 - Fibonacci Presents Seasonal 10 12.8% 81
Yet Another Contest 1 P2 - A Boring Problem YAC 10p 12.9% 86
COCI '19 Contest 4 #4 Klasika COCI 17p 12.9% 54
COCI '09 Contest 6 #6 Gremlini COCI 25p 12.9% 17
COCI '14 Contest 7 #6 Police COCI 30p 12.9% 32
COCI '16 Contest 4 #5 Rima COCI 17p 12.9% 15
NOI '22 Multi-Provincial Team Selection P4 - Card China NOI 25p 12.9% 5
TLE '16 Contest 2 P3 - Fax's Thanksgiving Dinner TLE 10p 12.9% 45
NOI '05 P1 - The Magnificent Waltz China NOI 20p 12.9% 46
Calendar Contest Problem 3 — Classical Maya Seasonal 10 12.9% 9
BPC 1 S3 - Bus Stops Uncategorized 17p 12.9% 25
NOI '14 P6 - Ticket Purchase China NOI 30p 13.0% 37
NOIP '18 P6 - Defending the Kingdom China NOI 25p 13.0% 5
Yet Another Contest 5 P2 - Big Score YAC 10p 13.0% 94
Cheerio Contest 2 P2 - Cereal Boxes Uncategorized 3 13.0% 25
Baltic OI '08 P6 - Gloves Baltic OI 17p 13.0% 19
Another Contest 9 Problem 4 - Alchemy ACC 10 13.0% 22
DMPG '19 G4 - Carpet Cleaning Chore DMOPC 12p 13.0% 10
CCC '98 S5 - Mountain Passage CCC 10 13.0% 148
Secret Santa Uncategorized 15 13.0% 20
Yet Another Contest 6 P3 - No More Cell Phone Messaging YAC 10p 13.0% 103
New Year's '18 P3 - World Domination Fun Seasonal 10p 13.0% 130
Mock CCC '23 1 S1 - Composite Fibonacci Numbers Mock CCC 5p 13.0% 148
COI '07 #3 Tamnica COCI 15p 13.0% 29
Bubble Cup V8 E Spectator Riots Bubble Cup 25 13.0% 3
WC '16 Contest 2 S3 - Turbolift Testing Woburn Challenge 15p 13.0% 17
MALD Contest 1 P3 - Scratch Cat and Infestation Uncategorized 7 13.0% 61
A Sum Problem Olympiads School 12p 13.0% 76
Fibonacci Sequence Uncategorized 15p 13.1% 781
CCO '03 P6 - Cheap Gas CCO 20p 13.1% 79
Magic Bits Uncategorized 10p 13.1% 40
COCI '12 Contest 2 #4 Popust COCI 10p 13.1% 40
Sword Art Online Judge 3 Seasonal 7 13.1% 33
COCI '20 Contest 5 #4 Planine COCI 17p 13.1% 18
Double Doors Regional P4 - Tudor Teaches Jason How To Be Productive Uncategorized 10 13.1% 40
WC '17 Contest 3 S3 - Down for Maintenance Woburn Challenge 15p 13.1% 8
HCI '16 - Jumping Uncategorized 20 13.1% 80
RGPC '17 P5 - Scrabble Nuts Uncategorized 12p 13.1% 211
TLE '16 Contest 3 P2 - In Remembrance TLE 5p 13.1% 67
CCO Preparation Test 2 P1 - Concatenation Mock CCO 17p 13.1% 32
DMOPC '20 Contest 3 P2 - Bob and Parallel-Ks DMOPC 7p 13.1% 160
UTS Open '21 P5 - State Taxes Uncategorized 17p 13.2% 42
DMOPC '21 Contest 2 P6 - Strange Function DMOPC 30p 13.2% 10
UCRPC F21 E - Feeding Friendsy ICPC 7p 13.2% 20
Back To School '16: Screensaver Seasonal 10 13.2% 97
DMOPC '18 Contest 5 P4 - An Art Gallery Problem DMOPC 12p 13.2% 73
GFSSOC '15 Winter J4 - Christmas Music GFSSOC 5p 13.2% 22