1009. Complement of Base 10 Integer: 10的補數

 1009. Complement of Base 10 Integer: 10的補數

The complement of an integer is the integer you get when you flip all the 0's to 1's and all the 1's to 0's in its binary representation.

• For example, The integer 5 is "101" in binary and its complement is "010" which is the integer 2.

Given an integer n, return its complement.

讓你算10的補數

我觀察了一下

發現就是找第一個s 使得 2**s-1>=n 然後用2**s-n-1即可

參考底下的python code:

class Solution:
    def bitwiseComplement(self, n: int) -> int:
        if n==0 or n==1:
            return 1-n
        s=1
        while True:
            s=2*s
            if s-1>=n:
                return s-1-n