local u,v = 1, 1

function R(seed)
    if seed then
        u = seed
        v = seed
    end

    v = 36969 * (v & 65535) + (v >> 16)
    u = 18000 * (u & 65535) + (u >> 16)

    return (math.abs((v<<16) +u)*0.000000001)%1
end