eval"N,S,*P="+`dd`.split*?,;g=->f,t,s=0,r=[],h=({}){h[s]||=[];h[s]<<r;(f...t).map{|i|g[i+1,t,s+P[i],r+[i+1],h]};h};r=[];g[0,N/2].map{|s,a|a.product(g[N/2,N][S-s]||[]){|x,y|r<<x+y}};puts r.sort.map{|a|a*" "}