#Cooley-Tukey
{.,.({[\.2%fft\(;2%fft@-1?-1\?-2?:w;.,,{w\?}%[\]zip{{*}*}%]zip.{{+}*}%\{{-}*}%+}{;}if}:fft;
[1 1 1 1 0 0 0 0]fft n*