Earned on 25 Nov 2012 for solving Problem 1. Times 2 - START HERE.
Earned on 25 Nov 2012 for liking Problem 25. Remove any row in which a NaN appears.
Earned on 25 Nov 2012 for commenting on Problem 9. Who Has the Most Change?.
Earned on 17 Dec 2012 for creating Problem 1124. String permutations on phone keyboard.
Earned on 2 May 2014 for first solving .
Earned on 30 Nov 2013 for solving all the problems in CUP Challenge.
Earned on 11 Jul 2013 for submitting the best solution .
Earned on 4 Dec 2016 at 16:48 for having 50 or more solvers for Problem 42632. Your favourite city!.
Earned on 15 Dec 2012 for solving all the problems in Tiles Challenge.
Earned on 16 Nov 2013 for solving all the problems in ASEE Challenge.
Earned on 14 Mar 2013 for solving all the problems in Cody Challenge.
Earned on 8 Dec 2013 for creating 10 problems.
Earned on 23 Apr 2013 for solving 500 problems.
Solve all the problems in Modeling and Simulation Challenge problem group.
Earned on 15 Sep 2015 for solving all the problems in Magic Numbers.
Must receive 25 total likes for the problems you created.
Must receive 50 total likes for the solutions you submitted.
Solve all the problems in Indexing I problem group.
Must receive 10 likes for a solution you submitted.
Must receive 10 likes for a problem you created.
Solve all the problems in Indexing II problem group.
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