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Problem Category Points AC % ▾ Users
CCO '04 P3 - S and K CCO 15p 4.5% 6
Waterloo 2023 Fall E - Loose Goose Waterloo Local 25 4.5% 1
DMOPC '21 Contest 4 P6 - Balanced Line DMOPC 35p 4.5% 4
Waterloo 2023 Winter E - Colourful Tree Waterloo Local 25 4.5% 4
SMAC 08/09 (Oct) #4 - Daycare Uncategorized 15p 4.5% 20
ETSR '23 Online Round 2 Problem 2 - Equation Uncategorized 15p 4.4% 35
MNYC '17: Skiing Competition Seasonal 15p 4.4% 7
CCO '99 P5 - Sum Of Products CCO 15 4.3% 1
Mock CCO '19 Contest 2 Problem 5 - A Geometry Problem Mock CCO 12p 4.3% 2
ETSR '23 Onsite Round 1 Problem 1 - Arithmetic Uncategorized 20p 4.3% 16
DMOPC '18 Contest 4 P6 - Dr. Henri and Resistor Chains DMOPC 20p 4.2% 10
The Contest Contest 1 P5 - A Typical CCO Problem Uncategorized 20p 4.2% 24
HCI '16 - Computation Uncategorized 0 4.2% 3
Bubble Cup V8 G Run for beer Bubble Cup 20 4.1% 17
CCC '00 S5 - Sheep and Coyotes CCC 10p 4.1% 177
Another Contest 1 Problem 3 - Poutine ACC 10 4.1% 58
ETSR '23 Onsite Round 2 Problem 2 - Exponents Uncategorized 25p 4.1% 13
COCI '22 Contest 5 #5 Zastave COCI 17p 4.1% 20
Bubble Cup V9 A Cowboy Beblop at his computer Bubble Cup 35 4.1% 9
Triway Cup '19 Summer D - Napping Seasonal 15p 4.1% 6
NOI '02 P5 - New Tetris China NOI 15p 4.1% 3
Maximum Deviation Spanning Tree Olympiads School 25p 4.0% 4
EGOI '23 P8 - Guessing Game EGOI 50p 4.0% 7
COCI '16 Contest 7 #5 Paralelogrami COCI 17p 4.0% 2
COCI '17 Contest 6 #6 Vrtić COCI 25p 4.0% 2
Baltic OI '18 P3 - Worm Worries Baltic OI 30p 4.0% 5
DMOPC '21 Contest 10 P4 - Bitwise Telephone DMOPC 17p 3.9% 31
CCO '06 P5 - Domino CCO 30 3.9% 3
Mock CCC '23 2 S3 - Richard The Penguin Mock CCC 10p 3.9% 13
Mock CCC '15 S5 - Kongou Mock CCC 40p 3.9% 13
Yet Another Contest 4 P4 - Even The Odds YAC 20p 3.9% 12
TLE '16 Contest 6 (Mock CCC) S5 - Toll Routes TLE 20p 3.9% 26
COI '19 #2 Pastiri COCI 35p 3.9% 4
CCC '20 J4 - Cyclic Shifts (Hard) CCC 12p 3.8% 36
Cheerio Contest 3 P5 - Train Network Uncategorized 20p 3.8% 16
CCO Preparation Test 2 P2 - Forest Area Mock CCO 25p 3.8% 5
Root Solver Uncategorized 30p 3.7% 9
Valentine's Day '15 P1 - #1 BABE Seasonal 15p 3.6% 2
WC '15 Contest 3 S4 - Lex Luthor's Landmines Woburn Challenge 30p 3.6% 6
IOI '11 P6 - Parrots IOI 20p 3.6% 16
OCC '19 G4 - Willson and Fighting Olympiads School 30p 3.5% 3
IOIQR P5 - Some Game Seasonal 25 3.5% 3
Calendar Contest Problem 6 — Ming Dynasty Seasonal 25 3.5% 2
NOI '16 P3 - The Beauty of Cycles China NOI 30p 3.4% 1
IOI '23 P6 - Robot Contest IOI 40p 3.4% 2
IOI '15 P3 - Teams (Standard I/O) IOI 35p 3.4% 37
The Contest Contest 1 P4 - A Typical YAC Problem Uncategorized 25p 3.4% 7
Catching Their Flights Uncategorized 0p 3.4% 11
Geometric Sequence Uncategorized 10 3.4% 8
DMOPC '19 Contest 4 P4 - Math Class DMOPC 15p 3.4% 16