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Problem Category Points AC % ▴ Users
Waterloo 2001 Winter B - Tight words Waterloo Local 7 66.7% 4
Waterloo 2013 Fall A - Compressed Words? Waterloo Local 5 44.4% 6
Waterloo 2013 Fall B - Java vs. Scheme Smackdown Waterloo Local 7 17.6% 3
Waterloo 2003 Spring B - Persistent Numbers Waterloo Local 5 57.1% 4
Waterloo 2001 Fall 1 A - Average Speed Waterloo Local 3 17.5% 8
Waterloo 2001 Fall 1 E - A Multiplication Game Waterloo Local 7 16.1% 3
Waterloo 2001 Fall 1 C - Babelfish Waterloo Local 5 28.9% 12
Waterloo 2005 Winter E - Traditional BINGO Waterloo Local 5 66.7% 4
ETSR '23 Onsite Round 2 Problem 1 - Bracket Uncategorized 12p 8.4% 26
UACC 1 P2 - Puzzling Parks Uncategorized 5 27.8% 207
ETSR '23 Online Round 2 Problem 3 - Stone Game Uncategorized 15p 5.2% 44
ETSR '23 Online Round 2 Problem 2 - Equation Uncategorized 15p 4.4% 35
ETSR '23 Online Round 2 Problem 1 - Pencil Uncategorized 3p 68.9% 144
ETSR '23 Online Round 2 Problem 4 - Queue Uncategorized 17p 5.0% 15
ETSR '23 Onsite Round 1 Problem 3 - Travel Uncategorized 17p 4.8% 20
ETSR '23 Onsite Round 1 Problem 2 - Origami Uncategorized 15p 21.0% 24
ETSR '23 Onsite Round 1 Problem 1 - Arithmetic Uncategorized 20p 4.3% 16
ETSR '23 Onsite Round 2 Problem 2 - Exponents Uncategorized 25p 4.1% 13
ETSR '23 Onsite Round 2 Problem 3 - Trees Uncategorized 30p 2.2% 8
UACC 1 P3 - Cheeky Checkers Uncategorized 7 60.1% 141
Counting Problem Uncategorized 17 45.5% 5
APIO '23 P1 - Cyberland APIO 17p 9.1% 33
APIO '23 P2 - Sequence APIO 25p 7.9% 17
APIO '23 P3 - Alice, Bob, and Circuit APIO 45p 0.0% 0
CCO '23 P1 - Binaria CCO 12p 23.2% 171
CCO '23 P2 - Real Mountains CCO 17p 13.8% 68
Geography Class Uncategorized 5p 14.1% 67
IOI '04 P3 - Polygon IOI 20p 3.1% 1
CTSC '15 P5 - Calendar Management China NOI 25 33.3% 1
Singularity Cup P5 - Perfect Matrix Uncategorized 20 21.7% 48
Singularity Cup P4 - Staircase Sum Uncategorized 17p 13.3% 65
Singularity Cup P6 - Explosive Breakout Uncategorized 30p 19.7% 15
NOI '17 P4 - Game China NOI 25p 16.7% 1
NOI '17 P5 - Vegetables China NOI 25p 66.7% 4
NOI '17 P6 - Magic China NOI 40p 40.0% 2
EGOI '23 P1 - Inflation EGOI 7p 27.9% 132
EGOI '23 P2 - Padel Prize Pursuit EGOI 10p 20.2% 32
EGOI '23 P3 - Find the Box EGOI 17p 16.4% 17
EGOI '23 P4 - Bikes vs Cars EGOI 20p 30.6% 10
EGOI '23 P6 - Candy EGOI 12p 22.0% 38
EGOI '23 P7 - Sopsug EGOI 17p 7.8% 13
NOI '17 P1 - Integers China NOI 20p 29.1% 10
NOI '17 P2 - Queue China NOI 20p 45.3% 9
NOI '17 P3 - Pool China NOI 30p 38.9% 3
JOI '23 Open P1 - Ancient Machine 2 JOI 20p 1.4% 1
JOI '23 Open P2 - Cell Automaton JOI 40p 0.0% 0
JOI '23 Open P3 - Garden JOI 12p 9.4% 5
NOI '23 P1 - Square Coloring China NOI 17p 52.6% 10
NOI '23 P2 - Osmanthus Tree China NOI 25p 26.3% 5
NOI '23 P3 - Depth First Search China NOI 35p 37.5% 2