Lambda's best friend

Solve at least 50 problems as official contestant in Haskell

cojna1, first achieved on July 23, 2012

ak464tnok1, first achieved on Jan. 31, 2017

autotaker1, first achieved on March 5, 2014

bjin1, first achieved on Nov. 15, 2011

Rotsor1, first achieved on Sept. 28, 2014

torus7111, first achieved on Nov. 23, 2016