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Problem Category Points AC % Users
NOI '05 P4 - CongCong and KoKo China NOI 15p 20.2% 62
NOI '07 P1 - Social Network China NOI 15p 32.4% 85
NOI '08 P1 - Masquerade Party China NOI 15p 9.4% 25
NOI '12 P1 - Random Number Generator China NOI 15p 25.1% 62
NOI '14 P4 - Zoo China NOI 15p 27.9% 79
NOI '14 P5 - Random Number Generator China NOI 12p 24.1% 52
NOI '15 P1 - Automated Program Analyzer China NOI 12p 18.7% 102
NOI '97 P5 - Building Game China NOI 15p 27.9% 25
NOI '97 P6 - Satellite Coverage China NOI 12p 38.4% 28
NOI '98 P2 - Free Pizza China NOI 15p 18.8% 13
NOI '98 P3 - Software Installation Disk China NOI 15p 43.8% 3
NOI '98 P4 - Scarf Cutting China NOI 15p 26.0% 9
NOI '98 P5 - SERNET Simulation China NOI 12p 8.5% 14
NOI '99 P2 - Nails and Ball China NOI 15p 20.5% 16
NOI '99 P4 - Chessboard Division China NOI 15p 18.6% 15
NOI '99 P5 - Optimally Connected Subset China NOI 15p 73.1% 19
NOIP '04 P4 - Bugs Eating Computation China NOI 15p 5.9% 10
NOIP '07 P3 - Removing Numbers from Matrix China NOI 15p 22.1% 25
NOIP '08 P3 - Message Passing China NOI 15p 44.4% 18
NOIP '15 P5 - Substring China NOI 12p 23.3% 19
NOIP '18 Junior P3 - Shuttle Bus China NOI 12p 13.0% 7
NOIP '20 P2 - String Matching China NOI 12p 12.2% 14
NOIP '20 P3 - Game of Moving Ball China NOI 15p 11.0% 7
NOIP '99 P1 - Missile Interception China NOI 12p 41.6% 42
NOIP '99 P3 - Traveller's Budget China NOI 12p 11.4% 13
NOIP '99 P4 - Stamp Face Value Design China NOI 12p 11.4% 10
ICPC NWERC 2015 E - Elementary Math ICPC 15 35.4% 6
OCC '19 S4 - Playing with Numbers Olympiads School 12p 12.0% 12
OCC '19 S5 - Partitioning Olympiads School 12p 8.9% 13
Bob's Kingdom Olympiads School 12p 16.2% 28
Adjacent Pairs Olympiads School 15p 10.4% 22
Tree Journey Olympiads School 12p 50.0% 34
Infinity Card Decks Olympiads School 15p 15.1% 18
City Travel Olympiads School 15p 17.8% 25
Three Colors Olympiads School 12p 48.2% 38
0-1 Sequence Olympiads School 15p 21.6% 5
Longest Up-Down Subsequence POI 12p 30.1% 131
A Fenwick Tree Question Olympiads School 15 31.4% 63
Another Small Favour Uncategorized 15p 5.3% 9
ICPC PACNW 2016 F - Illumination ICPC 12 21.0% 27
ICPC PACNW 2016 G - Maximum Islands ICPC 15 25.9% 7
ICPC PACNW 2016 I - Postman ICPC 12 25.3% 32
ICPC PACNW 2016 J - Shopping ICPC 15 23.5% 155
ICPC PACNW 2016 K - Tournament Wins ICPC 12 38.9% 9
ICPC PACNW 2016 L - Windy Path ICPC 15 22.6% 7
Path Finder 2: Electric Boogaloo Uncategorized 15p 19.4% 28
Power Eggs Uncategorized 15 34.5% 98
Perl Golf Uncategorized 15p 11.3% 41
Persuasion Uncategorized 12 30.2% 26
The Torture Chamber Uncategorized 15 16.9% 244