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Problem Category Points AC % ▾ Users
CCC '09 J1 - ISBN CCC 3 47.3% 3696
CCC '14 S1 - Party Invitation CCC 5 47.1% 3527
CCC '07 J1 - Who is in the Middle? CCC 3 47.0% 9182
CCC '24 J3 - Bronze Count CCC 5p 47.0% 484
CCC '11 J5 - Unfriend CCC 7 46.8% 1003
CCC '06 S4 - Groups CCC 10 46.5% 328
CCC '19 J3 - Cold Compress CCC 5 46.2% 3163
CCC '19 S1 - Flipper CCC 3p 46.1% 3955
CCC '97 S2 - Nasty Numbers CCC 5 46.0% 797
CCC '16 J3 - Hidden Palindrome CCC 5 45.9% 2562
CCC '13 S1 - From 1987 to 2013 CCC 5 45.8% 3925
CCC '20 J4 - Cyclic Shifts CCC 5p 45.7% 2291
CCC '12 S5 - Mouse Journey CCC 7 45.6% 1818
CCC '13 J2 - Rotating letters CCC 3 45.0% 4841
Mock CCC '14 J2 - Rope Unfolding Mock CCC 3 45.0% 285
Mock CCC '18 Contest 1 J1 - A String Problem Mock CCC 3p 45.0% 497
Mock CCC '18 Contest 5 J1 - Looking for the CCC Mock CCC 3p 44.7% 570
CCC '14 J2 - Vote Count CCC 3 44.5% 5375
CCC '13 J4 - Time on task CCC 5 44.5% 3017
Mock CCC '18 Contest 5 J4/S2 - Reverse Sort Mock CCC 5p 44.4% 261
CCC '11 J3 - Sumac Sequences CCC 5 43.3% 2875
CCC '05 S1 - Snow Calls CCC 5 43.3% 2278
CCC '08 J2 - Do the Shuffle CCC 3 43.3% 3440
CCC '98 S2 - Cross Number Puzzle CCC 5 43.1% 495
CCC '01 J2 - Mod Inverse CCC 3 42.9% 2538
CCC '20 J3 - Art CCC 3p 42.9% 2367
CCC '20 S1 - Surmising a Sprinter's Speed CCC 5p 42.8% 2047
CCC '13 S5 - Factor Solitaire CCC 15p 42.8% 735
CCC '08 J4 - From Prefix to Postfix CCC 7 42.8% 888
CCC '06 J4 - It's tough being a teen! CCC 7 41.5% 1242
CCC '06 J3 - Cell-Phone Messaging CCC 3 41.3% 1466
Mock CCC '19 Contest 1 S1 - Pusheen's Report Card Mock CCC 3p 41.3% 630
CCC '16 J1 - Tournament Selection CCC 3 41.2% 4717
CCC '01 S2 - Spirals CCC 5 41.2% 912
CCC '13 S3 - Chances of Winning CCC 10 41.2% 1365
Mock CCC '18 Contest 5 J5/S3 - Directed Graph Connectivity Mock CCC 7p 40.9% 487
CCC '05 J2 - RSA Numbers CCC 3 40.8% 2979
CCC '09 S2 - Lights Going On and Off CCC 10 40.6% 902
CCC '18 J1 - Telemarketer or not? CCC 3 40.1% 6894
Mock CCC '22 1 S3 - IU Mock CCC 7p 40.0% 194
Mock CCC '22 Contest 1 J1 - Square Root Decomposition Mock CCC 3 39.9% 666
CCC '02 S1 - The Students' Council Breakfast CCC 5 39.6% 1498
CCC '18 S2 - Sunflowers CCC 5p 39.5% 2811
CCC '15 J4 - Wait Time CCC 5 39.4% 1314
CCC '22 S1 - Good Fours and Good Fives CCC 5p 39.4% 2132
CCC '09 J2 - Old Fishin' Hole CCC 5 39.1% 1590
CCC '01 S3 - Strategic Bombing CCC 7 38.7% 1458
CCC '15 J3 - Rövarspråket CCC 5p 38.5% 2269
Mock CCC '23 Contest 1 J2 - Healthy Schedule Mock CCC 3 38.3% 561
CCC '23 J3 - Special Event CCC 5p 38.3% 1301