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Problem Category Points ▾ AC % Users
DMOPC '21 Contest 9 P4 - Ace of Diamonds DMOPC 20p 20.4% 43
Yet Another Contest 4 P4 - Even The Odds YAC 20p 3.8% 11
Yet Another Contest 4 P6 - No More Solitaire YAC 20p 6.6% 23
Yet Another Contest 4 P5 - Signpost YAC 20p 19.5% 25
CCO '22 P4 - Bi-ing Lottery Treekets CCO 20p 20.6% 29
CCO '22 P5 - Phone Plans CCO 20p 12.7% 31
A Math Contest P15 - Matrix Fixed Point Uncategorized 20 68.3% 30
APIO '22 P3 - Permutation APIO 20p 9.8% 12
DMOPC '21 Contest 10 P5 - Number Theory DMOPC 20p 43.4% 140
IOI '18 P4 - Mechanical Doll IOI 20p 22.6% 13
An Animal Contest 7 P4 - Squirrel Shenanigans AAC 20 19.2% 17
An Animal Contest 7 P6 - S-Squirrel? AAC 20p 11.4% 7
JOI '21 Open P1 - Crossing JOI 20p 42.9% 9
JOI '20 Open P1 - Furniture JOI 20p 35.0% 7
CEOI '22 P1 - Abracadabra CEOI 20p 20.6% 41
CEOI '22 P5 - Measures CEOI 20p 9.5% 28
Lemon Tree Uncategorized 20p 10.5% 14
Baltic OI '01 P3 - Box of Mirrors Baltic OI 20p 12.5% 7
Baltic OI '01 P2 - Crack the Code Baltic OI 20p 8.3% 1
NOI '16 P1 - Good Partitions China NOI 20p 7.8% 5
NOI '16 P4 - Interval China NOI 20p 21.6% 18
NOI '16 P5 - Drinking Water China NOI 20p 0.7% 1
SGS Programming Challenge P5 - Tree After School Uncategorized 20p 9.0% 7
Yet Another Contest 5 P5 - No More Concerts YAC 20p 10.7% 11
Yet Another Contest 8 P5 - Hidden Tree YAC 20p 5.0% 10
EGOI '22 P6 - Superpiece EGOI 20p 5.0% 8
Non-constructive Constant Time Algorithm Fun Math 20 9.1% 2
DMOPC '22 Contest 2 P4 - Falling Leaves DMOPC 20p 24.3% 28
DMOPC '22 Contest 3 P5 - Alice Rebalancing DMOPC 20p 7.3% 28
NOIP '20 P4 - WeRun China NOI 20p 5.0% 2
NOIP '22 P2 - Meow Meow China NOI 20p 5.1% 8
Cheerio Contest 3 P5 - Train Network Uncategorized 20p 3.8% 15
COCI '22 Contest 3 #5 Skrivača COCI 20p 20.2% 17
COCI '22 Contest 4 #4 Mreža COCI 20p 17.4% 22
CCC '23 S5 - The Filter CCC 20p 16.3% 86
Google Code Jam '22 Qualification Round Problem E - Twisty Little Passages Google Code Jam 20p 57.1% 3
Google Code Jam '08 Qualification Round Problem A - Fly Swatter Google Code Jam 20p 0.0% 0
Google Code Jam '08 Round 1A Problem C - Numbers Google Code Jam 20p 20.0% 3
Google Code Jam '10 Round 1A Problem C - Number Game Google Code Jam 20p 75.0% 3
Google Code Jam '22 Round 3 Problem B - Duck, Duck, Geese Google Code Jam 20p 50.0% 4
Google Code Jam '22 Round 1A Problem C - Weightlifting Google Code Jam 20p 75.0% 4
ETSR '23 Onsite Round 1 Problem 1 - Arithmetic Uncategorized 20p 4.3% 16
DMOPC '22 Contest 5 P6 - Threes and Twos DMOPC 20p 20.0% 54
IOI '04 P3 - Polygon IOI 20p 3.1% 1
Singularity Cup P5 - Perfect Matrix Uncategorized 20 21.7% 48
EGOI '23 P4 - Bikes vs Cars EGOI 20p 30.6% 10
NOI '17 P1 - Integers China NOI 20p 29.1% 10
NOI '17 P2 - Queue China NOI 20p 45.3% 9
JOI '23 Open P1 - Ancient Machine 2 JOI 20p 1.4% 1
NOI '23 P4 - Trade China NOI 20p 60.0% 6