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Problem Category Points ▴ AC % Users
A Fenwick Tree Question Olympiads School 15 30.0% 46
Baltic OI '06 P1 - Bitwise Expressions Baltic OI 15p 37.8% 9
Baltic OI '13 P2 - Palindrome-Free Numbers Baltic OI 15p 27.4% 85
COCI '17 Contest 7 #4 Clickbait COCI 15p 46.7% 6
DMOPC '19 Contest 3 P4 - Same Colour Leaves DMOPC 15 33.5% 120
Wesley's Anger Contest 2 Problem 3 - Pumpkin Counting WAC 15 22.6% 29
GlobeX Cup '19 J5 - Aliens Uncategorized 15 12.6% 19
Wesley++ Seasonal 15p 15.2% 10
JSB '19 - P5 CTF 15 19.2% 9
Longest Balanced Subsequence Uncategorized 15p 30.3% 28
DMOPC '19 Contest 4 P4 - Math Class DMOPC 15p 3.4% 16
Wesley's Anger Contest 3 Problem 5 - Triangle: The Root of All Evil WAC 15p 11.3% 40
COCI '19 Contest 5 #4 Putovanje COCI 15p 37.3% 100
Bitmask Magic Uncategorized 15p 30.0% 22
PIB '20 P7 - Karnaugh Maps Uncategorized 15p 8.5% 16
JOI '17 Final P4 - Commuter Pass JOI 15 22.9% 43
COCI '19 Contest 4 #3 Holding COCI 15p 29.4% 76
COCI '19 Contest 3 #3 Drvca COCI 15p 17.7% 33
COCI '19 Contest 3 #5 Sob COCI 15p 30.3% 34
COCI '19 Contest 6 #5 Trener COCI 15p 31.6% 68
COCI '19 Contest 1 #4 Trobojnica COCI 15p 14.6% 6
DMOPC '19 Contest 6 P4 - Grade 12 Math DMOPC 15p 23.4% 119
JOI '19 Final P3 - Collecting Stamps 3 JOI 15 25.4% 39
South African Computer Olympiad 2008 Day 1 Problem 3 - Visiting Grandma Uncategorized 15p 14.8% 76
Strategic Arrays Uncategorized 15p 32.3% 91
Willie's Subtree Uncategorized 15 16.8% 9
CCC '20 S2 - Escape Room (Hard) CCC 15p 5.6% 55
Facebook Hacker Cup '19 Final Round P1 - Strings as a Service FHC 15p 33.3% 4
COCI '11 Contest 6 #6 Košare COCI 15p 34.4% 74
CCO '20 P2 - Exercise Deadlines CCO 15p 29.7% 290
CCO '04 P3 - S and K CCO 15p 4.5% 6
CCO '04 P6 - Orko CCO 15 31.6% 42
COCI '09 Contest 2 #6 Pasijans COCI 15 25.6% 31
XIV POI Stage I - Queries POI 15p 0.5% 1
COCI '15 Contest 7 #5 Prosti COCI 15 18.2% 11
COCI '16 Contest 1 #6 Vještica COCI 15p 58.1% 21
COCI '09 Contest 4 #4 Ograda COCI 15p 22.9% 57
ACM U of T Tryouts C3 F - A Pleasant Stroll ICPC 15 17.2% 29
ACM U of T Tryouts C3 G - Office Mates ICPC 15 21.8% 34
ACM U of T Tryouts C2 E - MVP ICPC 15 27.2% 32
ACM U of T Tryouts C1 F - Foxic Expressions ICPC 15 15.1% 26
Return of the Digger Uncategorized 15p 6.8% 15
WC '18 Contest 1 S4 - Bad Influence Woburn Challenge 15p 12.4% 16
IOI '09 Practice Task 3 - Museum IOI 15p 48.5% 72
IOI '09 P6 - Mecho IOI 15 14.8% 324
NOI '98 P3 - Software Installation Disk China NOI 15p 43.8% 3
NOI '01 P4 - Applications of Arctangent China NOI 15 28.1% 81
NOI '01 P1 - Food Chain China NOI 15p 25.2% 82
NOI '99 P2 - Nails and Ball China NOI 15p 20.3% 15
NOI '01 P5 - Equation Solutions China NOI 15p 8.4% 67