def transpose(a)
    return a if a.empty?
        sub = a[0].size
        b = Array.new
        c = Array.new
        if a.size == 1
            a[0].each do |i|
                b << [i]
            end
            p b
        else
        for x in 0..a[0].size-1
         for y in 0..a.size-1
          b << a[y][x]
         end
        end

        until b.empty?
         c << b.take(a.size)
         a.size.times do
          b.delete_at(0)
         end
        end
           p c
      end
end