1218. 补数

class Solution:
    """
    @param num: an integer
    @return: the complement number
    """
    ‘‘‘
    大致思路:
    1.求出二进制位[2:]，然后replace,0和1，最后返回int(num,10)十进制位即可
    ‘‘‘
    def findComplement(self,num):
        bin_num = str(bin(num))[2:]
        bin_num = bin_num.replace(‘0‘,‘z‘)
        bin_num = bin_num.replace(‘1‘,‘0‘)
        bin_num = bin_num.replace(‘z‘,‘1‘)

        return int(bin_num,2)