def calcs(x,y,ax,ay,bx,by) ((ax-x)*(by-y)-(bx-x)*(ay-y))/2.0 end def inpf() a=gets.chomp.split(" ").map(&:to_f)end def inps() a=gets.chomp.split(" ")end def copy(a) Marshal.load(Marshal.dump(a)) end def kaizyo(n)(n < 2)? 1 : (2..n).inject(:*) end def scount(a) b=na(a.max+1);a.each{|n|b[n]+=1};return b end def na(n=0,d=0) Array.new(n,d)end def na2(n=0,m=0,d=0) Array.new(n){Array.new(m,d)}end def na3(n=0,m=0,l=0,d=0) Array.new(n){Array.new(m){Array.new(l,d)}}end def bit(n) n.to_s(2).split("").map(&:to_i) end def inp() a=gets.chomp.split(" ").map(&:to_i)end def ser(a,x,s) if(x >= a.size) @ans = [@ans,s].max return end if(x != 0) ser(a,x+1,s*a[x]) else ser(a,x+1,s+a[x]) end if((s > 0 and a[x] > 0) or (s < 0 and a[x] < 0)) ser(a,x+1,s+a[x]) else ser(a,x+1,s-a[x]) end end def ser2(a,x,s) if(x >= a.size) @ans = [@ans,s].max return end if(x != 0) ser(a,x+1,s/a[x]) else ser(a,x+1,s-a[x]) end if((s > 0 and a[x] > 0) or (s < 0 and a[x] < 0)) ser(a,x+1,s-a[x]) else ser(a,x+1,s+a[x]) end end @n = inp[0] t = inp t.delete(0) @ans = -1 ser(t,0,0) ser2(t,0,0) p @ans =begin =end