Computer Transformation（https://acs.jxnu.edu.cn/problem/HDU1041）

描述：
A sequence consisting of one digit, the number 1 is initially written into a computer. At each successive time step, the computer simultaneously tranforms each digit 0 into the sequence 1 0 and each digit 1 into the sequence 0 1. So, after the first time step, the sequence 0 1 is obtained; after the second, the sequence 1 0 0 1, after the third, the sequence 0 1 1 0 1 0 0 1 and so on. How many pairs of consequitive zeroes will appear in the sequence after n steps?
输入：

Computer Transformation（https://acs.jxnu.edu.cn/problem/HDU1041）最先出现在Python成神之路。