問題はここ
http://golf.shinh.org/p.rb?Maximum+Cyclic+Segment+Sum

手強い問題だ。
リストを網羅的に取り出すところで詰まっていたが、
そこまでは　何とか出来た。

【途中の調査ソース】

f[]=[]
f(x:s)=[[x]]++map(x:)(f s)
g[]=[]
g(x:s)=f(x:s)++g s
main=do l<-getLine;mapM print$g$(\s->s++init s)$words l

【入力】

100 200 300

【出力】

["100"]
["100","200"]
["100","200","300"]
["100","200","300","100"]
["100","200","300","100","200"]
["200"]
["200","300"]
["200","300","100"]
["200","300","100","200"]
["300"]
["300","100"]
["300","100","200"]
["100"]
["100","200"]
["200"]

【その後】

f[]=[]
f(x:s)=[[x]]++map(x:)(f s)
g[]=[]
g(x:s)=f(x:s)++g s
h[a]=a
h(a:b)|sum a>sum(b!!0)=h(a:tail b)|1>0=h b
main=do l<-getLine
	print$h$g$map read$(\s->s++init s)$words l

【入力】

1004 -2010 2008 -2011 1005

【出力】

[1005,1004]

あと、ちょっとで　サーバ通すぞ！！