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Problem Category Points AC % ▴ Users
Mock CCO '17 Problem 3 - Connection Mock CCO 20p 12.5% 38
CCO '11 P6 - Biggest (Zero Carbon) Footprint CCO 15p 12.6% 78
CCO '05 P4 - Primed Sequences CCO 12p 12.6% 92
CCO '15 P3 - Solar Flight CCO 20p 12.8% 68
CCO '09 P1 - Invasion of the Boxes CCO 20p 12.8% 22
CCO '22 P5 - Phone Plans CCO 20p 12.9% 32
CCO '03 P6 - Cheap Gas CCO 20p 13.1% 79
CCO Preparation Test 2 P1 - Concatenation Mock CCO 17p 13.1% 32
CCO Preparation Test 7 P2 - XOR Path Mock CCO 20p 13.5% 16
CCO Preparation Test 3 P1 - Primitive Pythagorean Pairs Mock CCO 25p 13.7% 20
CCO '23 P2 - Real Mountains CCO 17p 13.8% 68
Mock CCO '18 Contest 2 Problem 3 - Victor Trains Mock CCO 20p 14.0% 7
CCO '17 P3 - Vera and Modern Art CCO 30p 14.1% 93
CCO '05 P6 - Windows CCO 30p 14.2% 28
CCO '09 P4 - Bottle Caps CCO 20p 14.2% 37
CCO '04 P4 - Return of Space Turtle CCO 12 14.2% 46
Mock CCO '18 Contest 4 Problem 1 - Mining for Minerals Mock CCO 15p 14.2% 40
CCO '16 P2 - Splitting Hares CCO 15p 14.2% 89
Mock CCO '19 Contest 1 Problem 5 - A Tree Problem Mock CCO 25p 14.3% 6
CCO '07 P2 - Snowflakes CCO 10 14.4% 965
CCO '18 P4 - Gradient Descent CCO 15p 14.5% 251
Mock CCO '19 Contest 1 Problem 4 - A Chemistry Problem Mock CCO 15p 14.9% 13
CCO Preparation Test 3 P2 - Packing Up Mock CCO 25p 14.9% 117
CCO '01 P6 - Election Night CCO 15 15.2% 47
CCO '19 P4 - Card Scoring CCO 25p 15.3% 68
CCO '15 P2 - Artskjid CCO 15p 15.4% 503
CCO '18 P2 - Wrong Answer CCO 12p 15.4% 115
CCO '96 P6 - Hoppers CCO 15 15.5% 29
Mock CCO '18 Contest 3 Problem 6 - Roger Asks For More Marks Mock CCO 30p 15.5% 8
Mock CCO '19 Contest 2 Problem 6 - A Fundraising Problem Mock CCO 12p 15.8% 28
CCO '03 P5 - Longest Substring CCO 7p 15.8% 86
CCO '20 P5 - Interval Collection CCO 25p 16.0% 60
CCO '09 P6 - A Weighty Problem CCO 12p 16.1% 76
CCO '07 P5 - Particle Catcher CCO 30p 16.3% 10
Mock CCO '18 Contest 2 Problem 1 - Victor Runs Mock CCO 15p 16.5% 44
CCO Preparation Test 2 P3 - Subsets Mock CCO 20p 16.7% 39
CCO '23 P6 - Triangle Collection CCO 25p 16.7% 18
CCO '21 P1 - Swap Swap Sort CCO 17p 16.8% 152
CCO '01 P2 - Coke or Chocolate Milk CCO 12 17.1% 11
CCO '19 P3 - Winter Driving CCO 30p 17.1% 65
Mock CCO '17 Problem 4 - Guards Mock CCO 15p 17.2% 52
CCO '09 P5 - Parade CCO 17p 17.3% 43
Mock CCO '18 Contest 1 Problem 4 - A Rectangle Problem Mock CCO 25p 17.4% 7
CCO '18 P6 - Flop Sorting CCO 30p 17.5% 59
CCO '08 P2 - King & Weber CCO 10p 17.6% 69
Mock CCO '18 Contest 1 Problem 6 - A Combining Problem Mock CCO 15p 17.6% 78
CCO '17 P6 - Shifty Grid CCO 30p 17.8% 34
CCO '00 P6 - Extension Cords CCO 12 18.0% 7
CCO '18 P3 - Fun Palace CCO 30p 18.1% 76
CCO Preparation Test 3 P3 - Arrow Mock CCO 30p 18.1% 58