d=gets.to_i
x=gets.split.map{|e| e.to_i}.reverse
while x.size>3
	e=x.shift
	x[1]+=e
end
while x.size>0 && x[0]==0
	x.shift
end

if x.size==0
	puts "0"
	puts "0"
else
	puts x.size-1
	puts x.reverse*" "
end