If we want to be silly, here's an implementation which matches the original spec, but (a) does some unnecessary work, and (b) computes a result which might not have been desired.
hft=: <.@^@=@?~@# %~ |: + + Or, even sillier (and efficient!): hft=: $ $ 1: -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
